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<A HREF="#toc">Table of Contents</A><P>
 
<H2><A NAME="sect0" HREF="#toc0">Name</A></H2>
stripchart -  2D strip chart for plotting x and
y coordinate data. 
<H2><A NAME="sect1" HREF="#toc1">Synopsis</A></H2>
<B>stripchart<I> <I>pathName </I></I></B>?<I>option value</I>?... 
<H2><A NAME="sect2" HREF="#toc2">Description</A></H2>
The
<B>stripchart</B> command creates a strip chart for plotting two-dimensional data
(x,y coordinates). It has many configurable components: coordinate axes,
elements, legend, grid lines, cross hairs, etc.  They allow you to customize
the look and feel of the strip chart. <P>
The <B>stripchart</B> is essentially the
same as the <B>graph</B> widget.  It works almost exactly the very same way.   <P>
The
use of a strip chart differs in that the X-axis typically refers to time
points.  Data values are added at intervals.  The strip chart lets you automatically
maintain a view of the most recent time points. The axis options <B>-shiftby</B>
and <B>-autorange</B> control this. You can specify different line styles for data
points (see the  <B>-styles</B> option).   
<H2><A NAME="sect3" HREF="#toc3">Introduction</A></H2>
The <B>stripchart</B> command creates
a new window for plotting two-dimensional data (x,y coordinates).  Data points
are plotted in a box displayed in the center of the new window.  This is
the <I>plotting area</I>.  The coordinate axes are displayed in the margins around
the plotting area.  By default, the legend is displayed in the right margin.
 The title is displayed in top margin. <P>
A strip chart is composed of several
components: coordinate axes, data elements, legend, grid, cross hairs,
pens, postscript, and annotation markers.  
<DL>

<DT><I>axis</I>  </DT>
<DD>The stripchart widget can
display up to four coordinate axes (two X-coordinate and two Y-coordinate
axes), but you can create and use any number of axes. Axes control what
region of data is displayed and how the data is scaled. Each axis consists
of the axis line, title, major and minor ticks, and tick labels. Tick labels
display the value of each major tick. </DD>

<DT><I>crosshairs</I> </DT>
<DD>Cross hairs are used to
finely position the mouse pointer in relation to the coordinate axes. Two
perpendicular lines are drawn across the plotting area, intersecting at
the current location of the mouse pointer. </DD>

<DT><I>element</I>  </DT>
<DD>An element represents
a set of data points. Elements can be plotted  with a symbol at each data
point and lines connecting the points.  The appearance of the element, such
as its symbol, line width, and  color is configurable. </DD>

<DT><I>grid</I> </DT>
<DD>Extends the
major and minor ticks of the X-axis and/or Y-axis across the  plotting area.
 </DD>

<DT><I>legend</I>  </DT>
<DD>The legend displays the name and symbol of each data element. 
The legend can be drawn in any margin or in the plotting area. </DD>

<DT><I>marker</I> </DT>
<DD>Markers
are used annotate or highlight areas of the graph. For  example, you could
use a polygon marker to fill an area under a  curve, or a text marker to
label a particular data point. Markers  come in various forms: text strings,
bitmaps, connected line  segments, images, polygons, or embedded widgets.
</DD>

<DT><I>pen</I>  </DT>
<DD>Pens define attributes (both symbol and line style) for elements. 
Data elements use pens to specify how they should be drawn.  A data  element
may use many pens at once.  Here, the particular pen  used for a data point
is determined from each element's weight  vector (see the element's <B>-weight</B>
and <B>-style</B> options).   </DD>

<DT><I>postscript</I> </DT>
<DD>The widget can generate encapsulated PostScript
output. This component has several options to configure how the PostScript
is generated. </DD>
</DL>

<H2><A NAME="sect4" HREF="#toc4">Syntax</A></H2>
<BR>
<P>
<CODE><B>stripchart <I>pathName </I></B>?<I>option value</I>?...<BR>
</CODE><P>The <B>stripchart</B> command creates a new window <I>pathName</I> and makes it into
a <B>stripchart</B> widget.  At the time this command is invoked, there must not
exist a window named <I>pathName</I>, but <I>pathName</I>'s parent must exist.  Additional
options may may be specified on the command line or in the option database
to configure aspects of the strip chart such as its colors and font.  See
the <B>configure</B> operation below for the exact details as to what <I>option</I> and
<I>value</I> pairs are valid. <P>
If successful, <B>stripchart</B> returns the path name of
the widget.  It also creates a new Tcl command by the same name.  You can
use this command to perform various operations that query or modify the
graph. The general form is: <BR>
<P>
<CODE><I>pathName <I>operation</I></I> ?<I>arg</I>?...<BR>
</CODE><P>Both <I>operation</I> and its arguments determine the exact behavior of the command.
 The operations available for the strip chart are described in  the  <FONT SIZE=-1><B>STRIPCHART
OPERATIONS</B></FONT>
  section. <P>
The command can also be used to access components of
the strip chart. <BR>
<P>
<CODE><I>pathName component operation</I> ?<I>arg</I>?...<BR>
</CODE><P>The operation, now located after the name of the component, is the function
to be performed on that component. Each component has its own set of operations
that manipulate that component.  They will be described below in their own
sections. 
<H2><A NAME="sect5" HREF="#toc5">Example</A></H2>
The <B>stripchart</B> command creates a new strip chart.   <BR>
<CODE># Create a new strip chart.  Plotting area is black.<BR>
stripchart .s -plotbackground black<BR>
</CODE><P>A new Tcl command <I>.s</I> is also created.  This command can be used to query
and modify the strip chart.  For example, to change the title of the strip
chart to "My Plot", you use the new command and the widget's <B>configure</B> operation.
<BR>
<CODE># Change the title.<BR>
.s configure -title "My Plot"<BR>
</CODE><P>A strip chart has several components. To access a particular component you
use the component's name. For example, to add data elements, you use  the
new command and the <B>element</B> component. <BR>
<CODE># Create a new element named "line1"<BR>
.s element create line1 \<BR>
<tt>&#32;</tt>&nbsp;<tt>&#32;</tt>&nbsp;-xdata { 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 } \<BR>
<tt>&#32;</tt>&nbsp;<tt>&#32;</tt>&nbsp;-ydata { 26.18 50.46 72.85 93.31 111.86 128.47 143.14 <BR>
<tt>&#32;</tt>&nbsp;<tt>&#32;</tt>&nbsp;<tt>&#32;</tt>&nbsp;<tt>&#32;</tt>&nbsp;155.85 166.60 175.38 }<BR>
</CODE><P>The element's X and Y coordinates are specified using lists of numbers. 
Alternately, BLT vectors could be used to hold the X-Y coordinates. <BR>
<CODE># Create two vectors and add them to the strip chart.<BR>
vector xVec yVec<BR>
xVec set { 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 }<BR>
yVec set { 26.18 50.46 72.85 93.31 111.86 128.47 143.14 155.85 <BR>
<tt>&#32;</tt>&nbsp;<tt>&#32;</tt>&nbsp;166.60 175.38 }<BR>
.s element create line1 -xdata xVec -ydata yVec<BR>
</CODE><P>The advantage of using vectors is that when you modify one, the graph is
automatically redrawn to display the new values. <BR>
<CODE># Change the X-Y coordinates of the first point.<BR>
set xVec(0) 0.18<BR>
set yVec(0) 25.18<BR>
</CODE><P>An element named <I>line1</I> is now created in <I>.s</I>.  By default, the element's label
in the legend will be also <I>line1</I>. You can change the label, or specify no
legend entry, again using the element's <B>configure</B> operation. <BR>
<CODE># Don't display "line1" in the legend.<BR>
.s element configure line1 -label ""<BR>
</CODE><P>You can configure more than just the element's label.  An element has many
attributes such as symbol type and size, dashed or solid lines, colors,
line width, etc. <BR>
<CODE>.s element configure line1 -symbol square -color red \<BR>
<tt>&#32;</tt>&nbsp;<tt>&#32;</tt>&nbsp;-dashes { 2 4 2 } -linewidth 2 -pixels 2c<BR>
</CODE><P>Four coordinate axes are automatically created: <I>x</I>, <I>x2</I>, <I>y</I>, and <I>y2</I>.  And by
default, elements are mapped onto the axes <I>x</I> and <I>y</I>.  This can be changed
with the <B>-mapx</B> and <B>-mapy</B> options. <BR>
<CODE># Map "line1" on the alternate Y-axis "y2".<BR>
.s element configure line1 -mapy y2<BR>
</CODE><P>Axes can be configured in many ways too.  For example, you change the scale
of the Y-axis from linear to log using the <B>axis</B> operation. <BR>
<CODE># Y-axis is log scale.<BR>
.s axis configure y -logscale yes<BR>
</CODE><P>Axis limits are reset by simply specifying new axis limits using the <B>-min</B>
and <B>-max</B> configuration options. <BR>
<CODE>.s axis configure x -min 1.0 -max 1.5<BR>
.s axis configure y -min 12.0 -max 55.15<BR>
</CODE><P>By default, the limits of the axis are determined from data values. To reset
back to the default limits, set the <B>-min</B> and <B>-max</B> options to the empty value.
<BR>
<CODE># Reset the axes to autoscale again.<BR>
.s axis configure x -min {} -max {}<BR>
.s axis configure y -min {} -max {}<BR>
</CODE><P>It's common with strip charts to automatically maintain a view of the most
recent time points.  You can do this my setting the  <B>-autorange</B> option. <BR>
<CODE>.s axis configure x -autorange 20.0<BR>
</CODE><P>If the time points are added in X-coordinates 1.0 unit, only the last twenty
time points will be displayed.  As more data is added, the view will march
along. <P>
Sometimes the rate of data is so high that changing the axis limits
with each additional time point is prohibitive.  You can use the <B>-shiftby</B>
option to define an increment to shift the view when needed.   <BR>
<CODE>.s axis configure x -shiftby 15.0<BR>
</CODE><P>When the view is shifted, it will allow a range of 15 new time points to
be added until the axis limits are recomputed. <P>
By default, the legend is
displayed in the right margin.  You can change this or any other legend
configuration options using the <B>legend</B> component. <BR>
<CODE># Configure the legend font, color, and relief<BR>
.s legend configure -position left -relief raised \<BR>
<tt>&#32;</tt>&nbsp;<tt>&#32;</tt>&nbsp;-font fixed -fg blue<BR>
</CODE><P>To prevent the legend from being displayed, turn on the <B>-hide</B> option. <BR>
<CODE># Don't display the legend.<BR>
.s legend configure -hide yes<BR>
</CODE><P>The <B>stripchart</B> widget has simple drawing procedures called markers. They
can be used to highlight or annotate data in the strip chart. The types
of markers available are bitmaps, images, polygons, lines, or windows. Markers
can be used, for example, to mark or brush points.  Here  is a text marker
which labels the data first point.  Markers are created using the <B>marker</B>
operation. <BR>
<CODE># Create a label for the first data point of "line1".<BR>
.s marker create text -name first_marker -coords { 0.2 26.18 } \<BR>
<tt>&#32;</tt>&nbsp;<tt>&#32;</tt>&nbsp;-text "start" -anchor se -xoffset -10 -yoffset -10<BR>
</CODE><P>This creates a text marker named <I>first_marker</I>.  It will display the text
"start" near the coordinates of the first data point.  The <B>-anchor</B>, <B>-xoffset</B>,
and <B>-yoffset</B> options are used to display the marker above and to the left
of the data point, so that the actual data point isn't covered by the marker.
 By default, markers are drawn last, on top of data.  You can change this
with the <B>-under</B> option. <BR>
<CODE># Draw the label before elements are drawn.<BR>
.s marker configure first_marker -under yes<BR>
</CODE><P>You can add cross hairs or grid lines using the <B>crosshairs</B> and <B>grid</B> operations.
<BR>
<CODE># Display both cross hairs and grid lines.<BR>
.s crosshairs configure -hide no -color red<BR>
.s grid configure -hide no -dashes { 2 2 }<BR>
</CODE><P>Finally, to get hardcopy of the strip chart, use the <B>postscript</B> operation.
<BR>
<CODE># Print the strip chart into file "file.ps"<BR>
.s postscript output file.ps -maxpect yes -decorations no<BR>
</CODE><P>This generates a file <I>file.ps</I> containing the encapsulated PostScript of
the strip chart.  The option <B>-maxpect</B> says to scale the plot to the size
of the page.  Turning off the <B>-decorations</B> option indicates that no borders
or color backgrounds should be displayed (i.e. the background of the margins,
legend, and plotting area will be white). 
<H2><A NAME="sect6" HREF="#toc6">Stripchart Operations</A></H2>

<DL>

<DT><I>pathName
<B>axis <I>operation</I></B></I> ?<I>arg</I>?... </DT>
<DD>See the  <FONT SIZE=-1><B>AXIS COMPONENTS</B></FONT>
  section. </DD>

<DT><I>pathName <B>bar <I>elemName
</I></B></I>?<I>option value</I>?... </DT>
<DD>Creates a new barchart element <I>elemName</I>.  It's an error if
an element <I>elemName</I> already exists.   See the manual for <B>barchart</B> for details
about what <I>option</I> and <I>value</I> pairs are valid. </DD>

<DT><I>pathName <B>cget</B></I> <I>option</I> </DT>
<DD>Returns
the current value of the stripchart configuration option given by <I>option</I>.
 <I>Option</I> may be any option described below for the <B>configure</B> operation. </DD>

<DT><I>pathName
<B>configure </B></I>?<I>option value</I>?... </DT>
<DD>Queries or modifies the configuration options
of the strip chart.  If <I>option</I> isn't specified, a list describing all of
the current options for <I>pathName</I> is returned.  If <I>option</I> is specified, but
not <I>value</I>, then a list describing <I>option</I> is returned. If one or more <I>option</I>
and <I>value</I> pairs are specified, then for each pair, the stripchart option
<I>option</I> is set to <I>value</I>. The following options are valid for the stripchart.
<blockquote></DD>

<DT><B>-background <I>color</I></B> </DT>
<DD>Sets the background color. This includes the margins and
legend, but not the plotting area. </DD>

<DT><B>-borderwidth <I>pixels</I></B> </DT>
<DD>Sets the width of
the 3-D border around the outside edge of the widget.  The <B>-relief</B> option
determines if the border is to be drawn.  The default is <I>2</I>. </DD>

<DT><B>-bottommargin
<I>pixels</I></B> </DT>
<DD>Specifies the size of the margin below the X-coordinate axis.  If
<I>pixels</I> is <I>0</I>, the size of the margin is selected automatically. The default
is <I>0</I>. </DD>

<DT><B>-bufferelements <I>boolean</I></B> </DT>
<DD>Indicates whether to draw elements into a pixmap
before displaying them on the screen.  The advantage of buffering elements
is when markers are used heavily.  Markers can be moved and redrawn without
requiring every element to be redrawn again.  The disadvantage is that it
takes slightly longer to draw the graph. If <I>boolean</I> is true, data elements
are drawn to an internal pixmap.  The option should be turned off if the
plot is updated frequently. See the <FONT SIZE=-1><B>SPEED TIPS</B></FONT>
  section. The default is <I>1</I>.
</DD>

<DT><B>-buffergraph <I>boolean</I></B> </DT>
<DD>Indicates whether to draw the graph into a pixmap first.
If <I>boolean</I> is true, the entire graph is drawn into a pixmap and then copied
onto the screen.  This reduces flashing.  If false, the graph is  drawn directly
into the window.  Especially under Windows, turning off the  option can
be helpful when the stripchart is updated frequently.  Turning  off this
option also turns <B>-bufferelements</B> off. See the <FONT SIZE=-1><B>SPEED TIPS</B></FONT>
  section. The default
is <I>1</I>. </DD>

<DT><B>-cursor <I>cursor</I></B> </DT>
<DD>Specifies the widget's cursor.  The default cursor is
<I>crosshair</I>. </DD>

<DT><B>-font <I>fontName</I></B>  </DT>
<DD>Specifies the title font. The default is <I>*-Helvetica-Bold-R-Normal-*-18-180-*</I>.
</DD>

<DT><B>-halo <I>pixels</I></B>  </DT>
<DD>Specifies a maximum distance to consider when searching for
the closest data point (see the element's <B>closest</B> operation below). Data
points further than <I>pixels</I> away are ignored.  The default is <I>0.5i</I>. </DD>

<DT><B>-height
<I>pixels</I></B> </DT>
<DD>Specifies the requested height of widget.  The default is <I>4i</I>. </DD>

<DT><B>-invertxy
<I>boolean</I></B> </DT>
<DD>Indicates whether the placement X-axis and Y-axis should be inverted.
 If <I>boolean</I> is true, the X and Y axes are swapped.  The default is <I>0</I>. </DD>

<DT><B>-justify
<I>justify</I></B> </DT>
<DD>Specifies how the title should be justified.  This matters only
when the title contains more than one line of text. <I>Justify</I> must be <I>left</I>,
<I>right</I>, or <I>center</I>.  The default is <I>center</I>. </DD>

<DT><B>-leftmargin <I>pixels</I></B> </DT>
<DD>Sets the size
of the margin from the left edge of the window to  the Y-coordinate axis.
 If <I>pixels</I> is <I>0</I>, the size is calculated automatically.  The default is <I>0</I>.
</DD>

<DT><B>-plotbackground <I>color</I></B> </DT>
<DD>Specifies the background color of the plotting area.
 The default is <I>white</I>. </DD>

<DT><B>-plotborderwidth <I>pixels</I></B> </DT>
<DD>Sets the width of the 3-D border
around the plotting area.  The <B>-plotrelief</B> option determines if a border
is drawn.  The default is <I>2</I>. </DD>

<DT><B>-plotpadx <I>pad</I></B> </DT>
<DD>Sets the amount of padding to be
added to the left and right sides of the plotting area.  <I>Pad</I> can be a list
of one or two screen distances.  If <I>pad</I> has two elements, the left side
of the plotting area entry is padded by the first distance and the right
side by the second.  If <I>pad</I> is just one distance, both the left and right
sides are padded evenly.  The default is <I>8</I>. </DD>

<DT><B>-plotpady <I>pad</I></B> </DT>
<DD>Sets the amount
of padding to be added to the top and bottom of the plotting area.  <I>Pad</I>
can be a list of one or two screen distances.  If <I>pad</I> has two elements,
the top of the plotting area is padded by the first distance and the bottom
by the second.  If <I>pad</I> is just one distance, both the top and bottom are
padded evenly.  The default is <I>8</I>. </DD>

<DT><B>-plotrelief <I>relief</I></B> </DT>
<DD>Specifies the 3-D effect
for the plotting area.  <I>Relief</I> indicates how the interior of the plotting
area should appear relative to rest of the strip chart; for example, <I>raised</I>
means the plot should appear to protrude from the strip chart, relative
to the surface of the strip chart.  The default is <I>sunken</I>. </DD>

<DT><B>-relief <I>relief</I></B>
</DT>
<DD>Specifies the 3-D effect for the widget.  <I>Relief</I> indicates how the strip
chart should appear relative to widget it is packed into; for example,
<I>raised</I> means the strip chart should appear to protrude.  The default is
<I>flat</I>. </DD>

<DT><B>-rightmargin <I>pixels</I></B> </DT>
<DD>Sets the size of margin from the plotting area
to the right edge of the window.  By default, the legend is displayed in
this margin.  If <I>pixels</I> is than 1, the margin size is selected automatically.
</DD>

<DT><B>-takefocus</B> <I>focus</I>  </DT>
<DD>Provides information used when moving the focus from window
to window via keyboard traversal (e.g., Tab and Shift-Tab).  If <I>focus</I> is <I>0</I>,
this means that this window should be skipped entirely during keyboard
traversal.  <I>1</I> means that the this window should always receive the input
focus.  An empty value means that the traversal scripts make the decision
whether to focus on the window. The default is <I>""</I>. </DD>

<DT><B>-tile <I>image</I></B>  </DT>
<DD>Specifies
a tiled background.  If <I>image</I> isn't <I>""</I>, the background is tiled using <I>image</I>.
Otherwise, the normal background color is drawn (see the <B>-background</B> option).
 <I>Image</I> must be an image created using the Tk <B>image</B> command.  The default
is <I>""</I>. </DD>

<DT><B>-title <I>text</I></B>  </DT>
<DD>Sets the title to <I>text</I>. If <I>text</I> is <I>""</I>, no title will be
displayed. </DD>

<DT><B>-topmargin <I>pixels</I></B> </DT>
<DD>Specifies the size of the margin above the x2
axis.  If <I>pixels</I> is <I>0</I>, the margin size is calculated automatically. </DD>

<DT><B>-width
<I>pixels</I></B> </DT>
<DD>Specifies the requested width of the widget.  The default is <I>5i</I>. </DD>
</DL>
</blockquote>

<DL>

<DT><I>pathName
<B>crosshairs <I>operation </I></B></I>?<I>arg</I>? </DT>
<DD>See the  <FONT SIZE=-1><B>CROSSHAIRS COMPONENT</B></FONT>
  section. </DD>

<DT><I>pathName
<B>element <I>operation </I></B></I>?<I>arg</I>?... </DT>
<DD>See the  <FONT SIZE=-1><B>ELEMENT COMPONENTS</B></FONT>
  section. </DD>

<DT><I>pathName <B>extents
<I>item</I></B></I>  </DT>
<DD>Returns the size of a particular item in the strip chart.  <I>Item</I> must
be either <I>leftmargin</I>, <I>rightmargin</I>, <I>topmargin</I>, <I>bottommargin</I>, <I>plotwidth</I>,
or <I>plotheight</I>. </DD>

<DT><I>pathName <B>grid <I>operation </I></B></I>?<I>arg</I>?... </DT>
<DD>See the  <FONT SIZE=-1><B>GRID COMPONENT</B></FONT>
  section.
</DD>

<DT><I>pathName <B>invtransform <I>winX winY</I></B></I>  </DT>
<DD>Performs an inverse coordinate transformation,
mapping window coordinates back to graph coordinates, using the standard
X-axis and Y-axis. Returns a list of containing the graph coordinates. </DD>

<DT><I>pathName
<B>legend <I>operation </I></B></I>?<I>arg</I>?... </DT>
<DD>See the  <FONT SIZE=-1><B>LEGEND COMPONENT</B></FONT>
  section. </DD>

<DT><I>pathName <B>line
<I>elemName</I></B></I> ?<I>option value</I>?... </DT>
<DD>The operation is the same as <B>element</B>. </DD>

<DT><I>pathName <B>marker
<I>operation </I></B></I>?<I>arg</I>?... </DT>
<DD>See the  <FONT SIZE=-1><B>MARKER COMPONENTS</B></FONT>
  section. </DD>

<DT><I>pathName</I> <B>metafile</B> ?<I>fileName</I>?
</DT>
<DD><I>This operation is for Window platforms only</I>.   Creates a Windows enhanced
metafile of the stripchart. If present, <I>fileName</I> is the file name of the
new metafile. Otherwise, the metafile is automatically added to the clipboard.
</DD>

<DT><I>pathName <B>postscript <I>operation </I></B></I>?<I>arg</I>?... </DT>
<DD>See the  <FONT SIZE=-1><B>POSTSCRIPT COMPONENT</B></FONT>
  section.
</DD>

<DT><I>pathName <B>snap <I>photoName</I></B></I> </DT>
<DD>Takes a snapshot of the strip chart and stores
the contents in the photo image <I>photoName</I>.  <I>PhotoName</I> is the name of a Tk
photo image that must already exist. </DD>

<DT><I>pathName <B>transform <I>x y</I></B></I>  </DT>
<DD>Performs a
coordinate transformation, mapping graph coordinates to window coordinates,
using the standard X-axis and Y-axis. Returns a list containing the X-Y screen
coordinates. </DD>

<DT><I>pathName <B>xaxis <I>operation</I></B></I> ?<I>arg</I>?... </DT>
<DD></DD>

<DT><I>pathName <B>x2axis <I>operation</I></B></I> ?<I>arg</I>?...
 </DT>
<DD></DD>

<DT><I>pathName <B>yaxis <I>operation</I></B></I> ?<I>arg</I>?...  </DT>
<DD></DD>

<DT><I>pathName <B>y2axis <I>operation</I></B></I> ?<I>arg</I>?...  </DT>
<DD>See the
 <FONT SIZE=-1><B>AXIS COMPONENTS</B></FONT>
  section. </DD>
</DL>

<H2><A NAME="sect7" HREF="#toc7">Stripchart Components</A></H2>
A strip chart is composed
of several components: coordinate axes, data elements, legend, grid, cross
hairs, postscript, and annotation markers. Instead of one big set of configuration
options and operations, the strip chart is partitioned, where each component
has its own configuration options and operations that specifically control
that aspect or part of the strip chart.  
<H3><A NAME="sect8" HREF="#toc8">Axis Components</A></H3>
Four coordinate
axes are automatically created: two X-coordinate axes (<I>x</I> and <I>x2</I>) and two
Y-coordinate axes (<I>y</I>, and <I>y2</I>).  By default, the axis <I>x</I> is located in the
bottom margin, <I>y</I> in the left margin, <I>x2</I> in the top margin, and <I>y2</I> in the
right margin. <P>
An axis consists of the axis line, title, major and minor
ticks, and tick labels.  Major ticks are drawn at uniform intervals along
the axis.  Each tick is labeled with its coordinate value.  Minor ticks are
drawn at uniform intervals within major ticks.   <P>
The range of the axis controls
what region of data is plotted. Data points outside the minimum and maximum
limits of the axis are not plotted.  By default, the minimum and maximum
limits are determined from the data, but you can reset either limit. <P>
You
can create and use several axes. To create an axis, invoke the axis component
and its create operation. <BR>
<CODE># Create a new axis called "temperature"<BR>
.s axis create temperature<BR>
</CODE><P>You map data elements to an axis using the element's -mapy and -mapx configuration
options. They specify the coordinate axes an element is mapped onto. <BR>
<CODE># Now map the temperature data to this axis.<BR>
.s element create "temp" -xdata $x -ydata $tempData \<BR>
    -mapy temperature<BR>
</CODE><P>While you can have many axes, only four axes can be displayed simultaneously.
 They are drawn in each of the margins surrounding the plotting area.  The
axes x and y are drawn in the bottom and left margins. The axes x2 and y2
are drawn in top and right margins. Only x and y are shown by default. Note
that the axes can have different scales. <P>
To display a different axis, you
invoke one of the following components: <B>xaxis</B>, <B>yaxis</B>, <B>x2axis</B>, and <B>y2axis</B>.
The <B>use</B> operation designates the axis to be drawn in the corresponding
margin: <B>xaxis</B> in the bottom, <B>yaxis</B> in the left,  <B>x2axis</B> in the top, and
<B>y2axis</B> in the right. <BR>
<CODE># Display the axis temperature in the left margin.<BR>
.s yaxis use temperature<BR>
<P>
</CODE><P>You can configure axes in many ways. The axis scale can be linear or logarithmic.
 The values along the axis can either monotonically increase or decrease.
 If you need custom tick labels, you can specify a Tcl procedure to format
the label as you wish.  You can control how ticks are drawn, by changing
the major tick interval or the number of minor ticks.  You can define non-uniform
tick intervals, such as for time-series plots. <P>

<DL>

<DT><I>pathName <B>axis <B>cget <I>axisName
<I>option</I></I></B></B></I> </DT>
<DD>Returns the current value of the option given by <I>option</I> for <I>axisName</I>.
 <I>Option</I> may be any option described below for the axis <B>configure</B> operation.
</DD>

<DT><I>pathName <B>axis <B>configure <I>axisName </I></B></B></I>?<I>option value</I>?... </DT>
<DD>Queries or modifies the
configuration options of <I>axisName</I>.  If <I>option</I> isn't specified, a list describing
all the current options for <I>axisName</I> is returned.  If <I>option</I> is specified,
but not <I>value</I>, then a list describing <I>option</I> is returned.  If one or more
<I>option</I> and <I>value</I> pairs are specified, then for each pair, the axis option
<I>option</I> is set to <I>value</I>.   The following options are valid for axes. <blockquote></DD>

<DT><B>-autorange
<I>range</I></B>  </DT>
<DD>Sets the range of values for the axis to <I>range</I>.  The axis limits
are automatically reset  to display the most recent data points in this
range.   If <I>range</I> is 0.0, the range is determined from the limits of the
data.  If <B>-min</B> or <B>-max</B> are specified, they override this option.  The default
is <I>0.0</I>. </DD>

<DT><B>-color <I>color</I></B> </DT>
<DD>Sets the color of the axis and tick labels. The default
is <I>black</I>. </DD>

<DT><B>-command <I>prefix</I></B> </DT>
<DD>Specifies a Tcl command to be invoked when formatting
the axis tick labels. <I>Prefix</I> is a string containing the name of a Tcl proc
and any extra arguments for the procedure.  This command is invoked for
each major tick on the axis.  Two additional arguments are passed to the
procedure: the pathname of the widget and the current the numeric value
of the tick.  The procedure returns the formatted tick label.  If <I>""</I> is returned,
no label will appear next to the tick.  You can get the standard tick labels
again by setting <I>prefix</I> to <I>""</I>.  The default is <I>""</I>. <P>
Please note that this
procedure is invoked while the strip chart is redrawn. You may query the
configuration options.  But do not reset them, because  this can have unexpected
results. </DD>

<DT><B>-descending <I>boolean</I></B>  </DT>
<DD>Indicates whether the values along the axis
are monotonically increasing or decreasing.  If <I>boolean</I> is true, the axis
values will be decreasing.  The default is <I>0</I>. </DD>

<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates whether
the axis is displayed.  </DD>

<DT><B>-justify <I>justify</I></B> </DT>
<DD>Specifies how the axis title should
be justified.  This matters only when the axis title contains more than
one line of text. <I>Justify</I> must be <I>left</I>, <I>right</I>, or <I>center</I>.  The default is
<I>center</I>. </DD>

<DT><B>-limits <I>formatStr</I></B> </DT>
<DD>Specifies a printf-like description to format the
minimum and maximum limits of the axis.  The limits are displayed at the
top/bottom or left/right sides of the plotting area.  <I>FormatStr</I> is a list
of one or two format descriptions.  If one description is supplied, both
the minimum and maximum limits are formatted in the same way.  If two, the
first designates the format for the minimum limit, the second for the maximum.
 If <I>""</I> is given as either description, then  the that limit will not be
displayed.  The default is <I>""</I>. </DD>

<DT><B>-linewidth <I>pixels</I></B> </DT>
<DD>Sets the width of the axis
and tick lines.  The default is <I>1</I> pixel. </DD>

<DT><B>-logscale <I>boolean</I></B> </DT>
<DD>Indicates whether
the scale of the axis is logarithmic or linear.  If <I>boolean</I> is true, the
axis is logarithmic.  The default scale is linear. </DD>

<DT><B>-loose <I>boolean</I></B> </DT>
<DD>Indicates
whether the limits of the axis should fit the data points tightly, at the
outermost data points, or loosely, at the outer tick intervals. This is
relevant only when the axis limit is automatically calculated. If <I>boolean</I>
is true, the axis range is "loose". The default is <I>0</I>. </DD>

<DT><B>-majorticks <I>majorList</I></B>
</DT>
<DD>Specifies where to display major axis ticks.  You can use this option to
display ticks at non-uniform intervals.  <I>MajorList</I> is a list of axis coordinates
designating the location of major ticks.  No minor ticks are drawn.  If <I>majorList</I>
is <I>""</I>,  major ticks will be automatically computed. The default is <I>""</I>. </DD>

<DT><B>-max
<I>value</I></B> </DT>
<DD>Sets the maximum limit of <I>axisName</I>.  Any data point greater  than
<I>value</I> is not displayed.  If <I>value</I> is <I>""</I>,  the maximum limit is calculated
using the largest data value. The default is <I>""</I>. </DD>

<DT><B>-min <I>value</I></B> </DT>
<DD>Sets the minimum
limit of <I>axisName</I>. Any data point less than  <I>value</I> is not displayed.  If
<I>value</I> is <I>""</I>, the minimum limit is calculated using the smallest data value.
The default is <I>""</I>. </DD>

<DT><B>-minorticks <I>minorList</I></B> </DT>
<DD>Specifies where to display minor
axis ticks.  You can use this option to display minor ticks at non-uniform
intervals. <I>MinorList</I> is a list of real values, ranging from 0.0 to 1.0, designating
the placement of a minor tick.  No minor ticks are drawn if the <B>-majortick</B>
option is also set.  If <I>minorList</I> is <I>""</I>, minor ticks will be automatically
computed. The default is <I>""</I>. </DD>

<DT><B>-rotate <I>theta</I></B> </DT>
<DD>Specifies the how many degrees
to rotate the axis tick labels. <I>Theta</I> is a real value representing the number
of degrees to rotate the tick labels.  The default is <I>0.0</I> degrees. </DD>

<DT><B>-shiftby
<I>value</I></B> </DT>
<DD>Specifies how much to automatically shift the range of the axis. When
the new data exceeds the current axis maximum, the maximum is increased
in increments of <I>value</I>.  You can use this option to prevent the axis limits
from being recomputed at each new time point. If <I>value</I> is 0.0, then no automatic
shifting is done. The default is <I>0.0</I>. </DD>

<DT><B>-showticks <I>boolean</I></B> </DT>
<DD>Indicates whether
axis ticks should be drawn. If <I>boolean</I> is true, ticks are drawn.  If false,
only the axis line is drawn. The default is <I>1</I>. </DD>

<DT><B>-stepsize <I>value</I></B> </DT>
<DD>Specifies the
interval between major axis ticks.  If <I>value</I> isn't a valid interval (must
be less than the axis range),  the request is ignored and the step size
is automatically calculated. </DD>

<DT><B>-subdivisions <I>number</I></B>  </DT>
<DD>Indicates how many minor
axis ticks are to be drawn.  For example, if <I>number</I> is two, only one minor
tick is drawn.  If <I>number</I> is one, no minor ticks are displayed.  The default
is <I>2</I>. </DD>

<DT><B>-tickfont <I>fontName</I></B>  </DT>
<DD>Specifies the font for axis tick labels. The default
is <I>*-Courier-Bold-R-Normal-*-100-*</I>. </DD>

<DT><B>-ticklength <I>pixels</I></B> </DT>
<DD>Sets the length of major
and minor ticks (minor ticks are half the length of major ticks). If <I>pixels</I>
is less than zero, the axis will be inverted with ticks drawn pointing
towards the plot.  The default is <I>0.1i</I>. </DD>

<DT><B>-title <I>text</I></B> </DT>
<DD>Sets the title of the axis.
If <I>text</I> is  <I>""</I>, no axis title will be displayed.   </DD>

<DT><B>-titlecolor <I>color</I></B> </DT>
<DD>Sets
the color of the axis title. The default is <I>black</I>. </DD>

<DT><B>-titlefont <I>fontName</I></B>  </DT>
<DD>Specifies
the font for axis title. The default is <I>*-Helvetica-Bold-R-Normal-*-14-140-*</I>. </DD>
</DL>
<P>
Axis
configuration options may be also be set by the <B>option</B> command.  The resource
class is <I>Axis</I>.  The resource names are the names of the axes (such as <I>x</I>
or <I>x2</I>). <BR>
<CODE>option add *Stripchart.Axis.Color  blue<BR>
option add *Stripchart.x.LogScale  true<BR>
option add *Stripchart.x2.LogScale false<BR>
</blockquote>

<DL>

<DT></CODE><P><I>pathName <B>axis <B>create <I>axisName </I></B></B></I>?<I>option value</I>?... </DT>
<DD>Creates a new axis by the
name <I>axisName</I>.  No axis by the same name can already exist. <I>Option</I> and <I>value</I>
are described  in above in the axis <B>configure</B> operation. </DD>

<DT><I>pathName <B>axis <B>delete
</B></B></I>?<I>axisName</I>?... </DT>
<DD>Deletes the named axes. An axis is not really deleted until it
is not longer in use, so it's safe to delete axes mapped to elements. </DD>

<DT><I>pathName
<B>axis invtransform <I>axisName value</I></B></I> </DT>
<DD>Performs the inverse transformation, changing
the screen coordinate <I>value</I> to a graph coordinate, mapping the value mapped
to <I>axisName</I>.  Returns the graph coordinate. </DD>

<DT><I>pathName <B>axis limits <I>axisName</I></B></I>
</DT>
<DD>Returns a list of the minimum and maximum limits for <I>axisName</I>.  The order
of the list is <I>min max</I>. </DD>

<DT><I>pathName <B>axis names </B></I>?<I>pattern</I>?... </DT>
<DD>Returns a list of
axes matching zero or more patterns.  If no <I>pattern</I> argument is give, the
names of all axes are returned. </DD>

<DT><I>pathName <B>axis transform <I>axisName value</I></B></I> </DT>
<DD>Transforms
the coordinate <I>value</I> to a screen coordinate by mapping the it to <I>axisName</I>.
 Returns the transformed screen coordinate. </DD>
</DL>
<P>
Only four axes can be displayed
simultaneously.  By default, they are <I>x</I>, <I>y</I>, <I>x2</I>, and <I>y2</I>.  You can swap in
a different axis with <B>use</B> operation of the special axis components: <B>xaxis</B>,
<B>x2axis</B>, <B>yaxis</B>, and <B>y2axis</B>. <BR>
<CODE>.g create axis temp<BR>
.g create axis time<BR>
...<BR>
.g xaxis use temp<BR>
.g yaxis use time<BR>
</CODE><P>Only the axes specified for use are displayed on the screen. <P>
The <B>xaxis</B>,
<B>x2axis</B>, <B>yaxis</B>, and <B>y2axis</B> components operate on an axis location rather
than a specific axis like the more general <B>axis</B> component does.  The <B>xaxis</B>
component manages the X-axis located in the bottom margin (whatever axis
that happens to be).  Likewise, <B>yaxis</B> uses the Y-axis in the left margin,
<B>x2axis</B> the top X-axis, and <B>y2axis</B> the right Y-axis. <P>
They implicitly control
the axis that is currently using to that location.  By default, <B>xaxis</B> uses
the <I>x</I> axis, <B>yaxis</B> uses <I>y</I>, <B>x2axis</B> uses <I>x2</I>, and <B>y2axis</B> uses <I>y2</I>.  These components
can be more convenient to use than always determining what axes are current
being displayed by the graph. <P>
The following operations are available for
axes. They mirror exactly the operations of the <B>axis</B> component.  The <I>axis</I>
argument must be <B>xaxis</B>, <B>x2axis</B>, <B>yaxis</B>, or <B>y2axis</B>. 
<DL>

<DT><I>pathName <I>axis <B>cget <I>option</I></B></I></I>
</DT>
<DD></DD>

<DT><I>pathName <I>axis <B>configure </B></I></I>?<I>option value</I>?... </DT>
<DD></DD>

<DT><I>pathName <I>axis<B> invtransform <I>value</I></B></I></I>
</DT>
<DD></DD>

<DT><I>pathName <I>axis <B>limits</B></I></I> </DT>
<DD></DD>

<DT><I>pathName <I>axis<B> transform <I>value</I></B></I></I> </DT>
<DD></DD>

<DT><I>pathName <I>axis<B> use </B></I></I>?<I>axisName</I>?
  </DT>
<DD>Designates the axis <I>axisName</I> is to be displayed at this location.  <I>AxisName</I>
can not be already in use at another location.   This command returns the
name of the axis currently using this location. </DD>
</DL>

<H3><A NAME="sect9" HREF="#toc9">Crosshairs Component</A></H3>
Cross
hairs consist of two intersecting lines (one vertical and one horizontal)
drawn completely across the plotting area.  They are used to position the
mouse in relation to the coordinate axes.  Cross hairs differ from line
markers in that they are implemented using XOR drawing primitives. This
means that they can be quickly drawn and erased without redrawing the entire
strip chart. <P>
The following operations are available for cross hairs: 
<DL>

<DT><I>pathName
<B>crosshairs cget <I>option</I></B></I> </DT>
<DD>Returns the current value of the cross hairs configuration
option given by <I>option</I>.  <I>Option</I> may be any option described below for the
cross hairs <B>configure</B> operation. </DD>

<DT><I>pathName <B>crosshairs configure </B></I>?<I>option value</I>?...
  </DT>
<DD>Queries or modifies the configuration options of the cross hairs.  If
<I>option</I> isn't specified, a list describing all the current options for the
cross hairs is returned.  If <I>option</I> is specified, but not <I>value</I>, then a
list describing <I>option</I> is returned. If one or more <I>option</I> and <I>value</I> pairs
are specified, then for each pair, the cross hairs option <I>option</I> is set
to <I>value</I>. The following options are available for cross hairs. <blockquote></DD>

<DT><B>-color <I>color</I></B>
 </DT>
<DD>Sets the color of the cross hairs.  The default is <I>black</I>. </DD>

<DT><B>-dashes <I>dashList</I></B>
</DT>
<DD>Sets the dash style of the cross hairs. <I>DashList</I> is a list of up to 11 numbers
that alternately represent the lengths of the dashes and gaps on the cross
hair lines.  Each number must be between 1 and 255.  If <I>dashList</I> is <I>""</I>, the
cross hairs will be solid lines. </DD>

<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates whether cross hairs
are drawn. If <I>boolean</I> is true, cross hairs are not drawn.  The default is
<I>yes</I>. </DD>

<DT><B>-linewidth <I>pixels</I></B> </DT>
<DD>Set the width of the cross hair lines.  The default
is <I>1</I>. </DD>

<DT><B>-position <I>pos</I></B>  </DT>
<DD>Specifies the screen position where the cross hairs
intersect. <I>Pos</I> must be in the form "<I>@x,y</I>", where <I>x</I> and <I>y</I> are the window
coordinates of the intersection. </DD>
</DL>
<P>
Cross hairs configuration options may be
also be set by the <B>option</B> command.  The resource name and class are <I>crosshairs</I>
and <I>Crosshairs</I> respectively. <BR>
<CODE>option add *Stripchart.Crosshairs.LineWidth 2<BR>
option add *Stripchart.Crosshairs.Color     red<BR>
</blockquote>

<DL>

<DT></CODE><P><I>pathName <B>crosshairs off</B></I> </DT>
<DD>Turns of the cross hairs.  </DD>

<DT><I>pathName <B>crosshairs on</B></I>
</DT>
<DD>Turns on the display of the cross hairs. </DD>

<DT><I>pathName <B>crosshairs toggle</B></I>  </DT>
<DD>Toggles
the current state of the cross hairs, alternately mapping and unmapping
the cross hairs. </DD>
</DL>

<H3><A NAME="sect10" HREF="#toc10">Element Components</A></H3>
A data element represents a set of data.
 It contains x and y vectors containing the coordinates of the data points.
 Elements can be displayed with a symbol at each data point and lines connecting
the points.  Elements also control the appearance of the data, such as the
symbol type, line width, color etc. <P>
When new data elements are created,
they are automatically added to a list of displayed elements.   The display
list controls what elements are drawn and in what order.   <P>
The following
operations are available for elements. 
<DL>

<DT><I>pathName <B>element activate <I>elemName
</I></B></I>?<I>index</I>?... </DT>
<DD>Specifies the data points of element <I>elemName</I> to be drawn using
active foreground and background colors.  <I>ElemName</I> is the name of the element
and <I>index</I> is a number representing the index of the data point. If no indices
are present then all data points become active. </DD>

<DT><I>pathName <B>element cget <I>elemName
<I>option</I></I></B></I> </DT>
<DD>Returns the current value of the element configuration option given
by  <I>option</I>.  <I>Option</I> may be any option described below for the element <B>configure</B>
operation. </DD>

<DT><I>pathName <B>element closest <I>x y</I></B></I> <I>varName</I> ?<I>option value</I>?... ?<I>elemName</I>?...
</DT>
<DD>Finds the data point closest to the window coordinates <I>x</I> and <I>y</I> in the element
<I>elemName</I>.  <I>ElemName</I> is the name of an element, that must not be hidden. 
If no elements are specified, then all visible elements are searched.  It
returns via the array variable <I>varName</I> the name of the closest element,
the index of its closest point, and the graph coordinates of the point.
Returns <I>0</I>, if no data point within the threshold distance can be found,
otherwise <I>1</I> is returned.  The following <I>option</I>-<I>value</I> pairs are available.
<blockquote></DD>

<DT><B>-halo <I>pixels</I></B> </DT>
<DD>Specifies a threshold distance where selected data points are
ignored. <I>Pixels</I> is a valid screen distance, such as <I>2</I> or <I>1.2i</I>. If this option
isn't specified, then it defaults to the value of the stripchart's <B>-halo</B> option.
</DD>

<DT><B>-interpolate <I>boolean</I></B> </DT>
<DD>Indicates that both the data points and interpolated
points along the line segment formed should be considered.  If <I>boolean</I> 
is true, the closest line segment will be selected instead of the closest
point. If this option isn't specified, <I>boolean</I> defaults  to <I>0</I>. </DD>
</DL>
</blockquote>

<DL>

<DT><I>pathName <B>element
configure <I>elemName </I></B></I>?<I>option value</I>?... </DT>
<DD>Queries or modifies the configuration
options for elements.  If <I>option</I> isn't specified, a list describing all the
current options for <I>elemName</I> is returned.  If <I>option</I> is specified, but not
<I>value</I>, then a list describing the option <I>option</I> is returned.  If one or
more <I>option</I> and <I>value</I> pairs are specified, then for each pair, the element
option <I>option</I> is set to <I>value</I>.  The following options are valid for elements.
<blockquote></DD>

<DT><B>-activepen <I>penName</I></B> </DT>
<DD>Specifies pen to use to draw active element.  If <I>penName</I>
is <I>""</I>, no active elements will be drawn.  The default is  <I>activeLine</I>. </DD>

<DT><B>-color
<I>color</I></B>  </DT>
<DD>Sets the color of the traces connecting the data points.   </DD>

<DT><B>-dashes
<I>dashList</I></B> </DT>
<DD>Sets the dash style of element line. <I>DashList</I> is a list of up to
11 numbers that alternately represent the lengths of the dashes and gaps
on the element line.  Each number must be between 1 and 255.  If <I>dashList</I>
is <I>""</I>, the lines will be solid. </DD>

<DT><B>-data <I>coordList</I></B> </DT>
<DD>Specifies the X-Y coordinates
of the data.  <I>CoordList</I> is a list of numeric expressions representing the
X-Y coordinate pairs of each data point. </DD>

<DT><B>-fill <I>color</I></B>  </DT>
<DD>Sets the interior color
of symbols.  If <I>color</I> is <I>""</I>, then the interior of the symbol is transparent.
 If <I>color</I> is <I>defcolor</I>, then the color will be the same as the <B>-color</B> option.
 The default is <I>defcolor</I>. </DD>

<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates whether the element is
displayed.  The default is <I>no</I>. </DD>

<DT><B>-label <I>text</I></B> </DT>
<DD>Sets the element's label in the
legend.  If <I>text</I> is <I>""</I>, the element will have no entry in the legend. The
default label is the element's name. </DD>

<DT><B>-linewidth <I>pixels</I></B>  </DT>
<DD>Sets the width of
the connecting lines between data points.  If <I>pixels</I> is <I>0</I>, no connecting
lines will be drawn between symbols.  The default is <I>0</I>. </DD>

<DT><B>-mapx <I>xAxis</I></B> </DT>
<DD>Selects
the X-axis to map the element's X-coordinates onto. <I>XAxis</I> must be the name
of an axis.  The default is <I>x</I>. </DD>

<DT><B>-mapy <I>yAxis</I></B> </DT>
<DD>Selects the Y-axis to map the element's
Y-coordinates onto. <I>YAxis</I> must be the name of an axis. The default is <I>y</I>. </DD>

<DT><B>-offdash
<I>color</I></B> </DT>
<DD>Sets the color of the stripes when traces are dashed (see the <B>-dashes</B>
option).  If <I>color</I> is <I>""</I>, then the "off" pixels will represent gaps instead
of stripes.  If <I>color</I> is <I>defcolor</I>, then the color will be the same as the
<B>-color</B> option.  The default is <I>defcolor</I>. </DD>

<DT><B>-outline <I>color</I></B>  </DT>
<DD>Sets the color or
the outline around each symbol.  If <I>color</I> is <I>""</I>, then no outline is drawn.
If <I>color</I> is <I>defcolor</I>, then the color will be the same as the <B>-color</B> option.
 The default is <I>defcolor</I>. </DD>

<DT><B>-outlinewidth <I>pixels</I></B>  </DT>
<DD>Sets the width of the outline
bordering each symbol.  If <I>pixels</I> is <I>0</I>, no outline will be drawn. The default
is <I>1</I>. </DD>

<DT><B>-pixels <I>pixels</I></B> </DT>
<DD>Sets the size of symbols.  If <I>pixels</I> is <I>0</I>, no symbols
will be drawn.  The default is <I>0.125i</I>. </DD>

<DT><B>-scalesymbols <I>boolean</I></B>  </DT>
<DD>If <I>boolean</I> is
true, the size of the symbols drawn for <I>elemName</I> will change with scale
of the X-axis and Y-axis. At the time this option is set, the current ranges
of the axes are saved as the normalized scales (i.e scale factor is 1.0)
and the element is drawn at its designated size (see the <B>-pixels</B> option).
 As the scale of the axes change, the symbol will be scaled according to
the smaller of the X-axis and Y-axis scales.  If <I>boolean</I> is false, the element's
symbols are drawn at the designated size, regardless of axis scales.  The
default is <I>0</I>. </DD>

<DT><B>-smooth <I>smooth</I></B>  </DT>
<DD>Specifies how connecting line segments are
drawn between data points. <I>Smooth</I> can be either <I>linear</I>, <I>step</I>, <I>natural</I>, or
<I>quadratic</I>.  If <I>smooth</I> is <I>linear</I>, a single line segment is drawn, connecting
both data points. When <I>smooth</I> is <I>step</I>, two line segments are drawn. The first
is a horizontal line segment which steps the next x-coordinate.  The second
is a vertical line, moving to the next y-coordinate.  Both <I>natural</I> and <I>quadratic</I>
generate multiple segments between data points.  If <I>natural</I>, the segments
are generated using a cubic spline.  If <I>quadratic</I>, a quadratic spline is
used.  The default is <I>linear</I>. </DD>

<DT><B>-styles <I>styleList</I></B>  </DT>
<DD>Specifies what pen to use
based upon the range of weights given. <I>StyleList</I> is a list of style specifications.
Each style specification, in turn, is a list consisting of a pen name,
and optionally a minimum and maximum range.  Data points whose weight (see
the <B>-weight</B> option) falls in this range, are drawn with this pen.  If no
range is specified it defaults to the number of the pen in the list.  </DD>

<DT><B>-symbol
<I>symbol</I></B>  </DT>
<DD>Specifies the symbol for data points.  <I>Symbol</I> can be either <I>square</I>,
<I>circle</I>, <I>diamond</I>, <I>plus</I>, <I>cross</I>, <I>splus</I>, <I>scross</I>, <I>triangle</I>, <I>""</I> (where no symbol
is drawn), or a bitmap.  Bitmaps are specified as "<I>source</I> ?<I>mask</I>?", where
<I>source</I> is the name of the bitmap, and <I>mask</I> is the bitmap's optional mask.
 The default is <I>circle</I>. </DD>

<DT><B>-weights <I>wVec</I></B>  </DT>
<DD>Specifies the weights of the individual
data points.  This, in conjunction with the list pen styles (see the <B>-styles</B>
option) controls how data points are drawn.  <I>WVec</I> is the name of a BLT vector
or a list of numeric expressions representing the weights for each data
point. </DD>

<DT><B>-xdata <I>xVec</I></B>  </DT>
<DD>Specifies the x-coordinates of the data.  <I>XVec</I> is the name
of a BLT vector or a list of numeric expressions. </DD>

<DT><B>-ydata <I>yVec</I></B>  </DT>
<DD>Specifies
the y-coordinates of the data.  <I>YVec</I> is the name of a BLT vector or a list
of numeric expressions. </DD>
</DL>
<P>
Element configuration options may also be set by
the <B>option</B> command.  The resource class is <I>Element</I>. The resource name is
the name of the element. <BR>
<CODE>option add *Stripchart.Element.symbol line<BR>
option add *Stripchart.e1.symbol line<BR>
</blockquote>

<DL>

<DT></CODE><P><I>pathName <B>element create <I>elemName</I></B></I> ?<I>option value</I>?... </DT>
<DD>Creates a new element <I>elemName</I>.
 It's an error is an element <I>elemName</I> already exists.  If additional arguments
are present, they specify options valid for  element <B>configure</B> operation.
</DD>

<DT><I>pathName <B>element deactivate <I>elemName</I></B></I> ?<I>elemName</I>?... </DT>
<DD>Deactivates all the elements
matching <I>pattern</I>. Elements whose names match any of the patterns given are
redrawn using their normal colors. </DD>

<DT><I>pathName <B>element delete</B></I> ?<I>elemName</I>?... </DT>
<DD>Deletes
all the named elements.  The graph is automatically redrawn. </DD>

<DT><I>pathName <B>element
exists <I>elemName</I></B></I> </DT>
<DD>Returns <I>1</I> if an element <I>elemName</I> currently exists and <I>0</I>
otherwise. </DD>

<DT><I>pathName <B>element names </B></I>?<I>pattern</I>?...   </DT>
<DD>Returns the elements matching
one or more pattern.  If no <I>pattern</I> is given, the names of all elements
is returned. </DD>

<DT><I>pathName <B>element show</B></I> ?<I>nameList</I>?   </DT>
<DD>Queries or modifies the
element display list.  The element display list designates the elements
drawn and in what order. <I>NameList</I> is a list of elements to be displayed
in the order they are named.  If there is no <I>nameList</I> argument, the current
display list is returned. </DD>

<DT><I>pathName <B>element type</B></I> <I>elemName</I> </DT>
<DD>Returns the type
of <I>elemName</I>.  If the element is a bar element, the commands returns the
string <I>"bar"</I>, otherwise it returns <I>"line"</I>. </DD>
</DL>

<H3><A NAME="sect11" HREF="#toc11"></CODE><P>Grid Component</A></H3>
Grid lines extend
from the major and minor ticks of each axis horizontally or vertically
across the plotting area.  The following operations are available for grid
lines. 
<DL>

<DT><I>pathName <B>grid cget <I>option</I></B></I> </DT>
<DD>Returns the current value of the grid line
configuration option given by  <I>option</I>.  <I>Option</I> may be any option described
below for the grid <B>configure</B> operation. </DD>

<DT><I>pathName <B>grid configure</B></I> ?<I>option
value</I>?... </DT>
<DD>Queries or modifies the configuration options for grid lines.  If
<I>option</I> isn't specified, a list describing all the current grid options for
<I>pathName</I> is returned.  If <I>option</I> is specified, but not <I>value</I>, then a list
describing <I>option</I> is returned.  If one or more <I>option</I> and <I>value</I> pairs are
specified, then for each pair, the grid line option <I>option</I> is set to <I>value</I>.
 The following options are valid for grid lines. <blockquote></DD>

<DT><B>-color <I>color</I></B>  </DT>
<DD>Sets the color
of the grid lines.  The default is <I>black</I>. </DD>

<DT><B>-dashes <I>dashList</I></B> </DT>
<DD>Sets the dash style
of the grid lines. <I>DashList</I> is a list of up to 11 numbers that alternately
represent the lengths of the dashes and gaps on the grid lines.  Each number
must be between 1 and 255. If <I>dashList</I> is <I>""</I>, the grid will be solid lines.
</DD>

<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates whether the grid should be drawn. If <I>boolean</I> is true,
grid lines are not shown. The default is <I>yes</I>. </DD>

<DT><B>-linewidth <I>pixels</I></B> </DT>
<DD>Sets the width
of grid lines.  The default width is <I>1</I>. </DD>

<DT><B>-mapx <I>xAxis</I></B> </DT>
<DD>Specifies the X-axis to
display grid lines.  <I>XAxis</I> must be the name of an axis.  The default is <I>x</I>.
</DD>

<DT><B>-mapy <I>yAxis</I></B> </DT>
<DD>Specifies the Y-axis to display grid lines.  <I>YAxis</I> must be the
name of an axis. The default is <I>y</I>. </DD>

<DT><B>-minor <I>boolean</I></B> </DT>
<DD>Indicates whether the grid
lines should be drawn for minor ticks.  If <I>boolean</I> is true, the lines will
appear at minor tick intervals.  The default is <I>1</I>. </DD>
</DL>
<P>
Grid configuration options
may also be set by the  <B>option</B> command.  The resource name and class are
<I>grid</I> and  <I>Grid</I> respectively.  <BR>
<CODE>option add *Stripchart.grid.LineWidth 2<BR>
option add *Stripchart.Grid.Color     black<BR>
</blockquote>

<DL>

<DT></CODE><P><I>pathName <B>grid off</B></I> </DT>
<DD>Turns off the display the grid lines. </DD>

<DT><I>pathName <B>grid on</B></I>
</DT>
<DD>Turns on the display the grid lines. </DD>

<DT><I>pathName <B>grid toggle</B></I> </DT>
<DD>Toggles the display
of the grid.   </DD>
</DL>

<H3><A NAME="sect12" HREF="#toc12">Legend Component</A></H3>
The legend displays a list of the data elements.
 Each entry consists of the element's symbol and label.  The legend can appear
in any margin (the default location is in the right margin).  It can also
be positioned anywhere within the plotting area. <P>
The following operations
are valid for the legend. 
<DL>

<DT><I>pathName <B>legend activate <I>pattern</I></B></I>... </DT>
<DD>Selects legend
entries to be drawn using the active legend colors and relief. All entries
whose element names match <I>pattern</I>  are selected.  To be selected, the element
name must match only one <I>pattern</I>.  </DD>

<DT><I>pathName <B>legend cget <I>option</I></B></I> </DT>
<DD>Returns the
current value of a legend configuration option. <I>Option</I> may be any option
described below in the legend <B>configure</B> operation. </DD>

<DT><I>pathName <B>legend configure
</B></I>?<I>option value</I>?... </DT>
<DD>Queries or modifies the configuration options for the legend.
 If <I>option</I> isn't specified, a list describing the current legend options
for <I>pathName</I> is returned.  If <I>option</I> is specified, but not <I>value</I>, then a
list describing <I>option</I> is returned.  If one or more <I>option</I> and <I>value</I> pairs
are specified, then for each pair, the legend option <I>option</I> is set to <I>value</I>.
 The following options are valid for the legend. <blockquote></DD>

<DT><B>-activebackground <I>color</I></B>
</DT>
<DD>Sets the background color for active legend entries.  All legend entries
marked active (see the legend <B>activate</B> operation) are drawn using this
background color. </DD>

<DT><B>-activeborderwidth <I>pixels</I></B> </DT>
<DD>Sets the width of the 3-D border
around the outside edge of the active legend entries.  The default is <I>2</I>.
</DD>

<DT><B>-activeforeground <I>color</I></B> </DT>
<DD>Sets the foreground color for active legend entries.
 All legend entries marked as active (see the legend <B>activate</B> operation)
are drawn using this foreground color. </DD>

<DT><B>-activerelief <I>relief</I></B>  </DT>
<DD>Specifies the
3-D effect desired for active legend entries. <I>Relief</I> denotes how the interior
of the entry should appear relative to the legend; for example, <I>raised</I>
means the entry should appear to protrude from the legend, relative to
the surface of the legend.  The default is <I>flat</I>. </DD>

<DT><B>-anchor <I>anchor</I></B> </DT>
<DD>Tells how
to position the legend relative to the positioning point for the legend.
 This is dependent on the value of the <B>-position</B> option.  The default is
<I>center</I>. <blockquote></DD>

<DT><I>left</I> or <I>right</I> </DT>
<DD>The anchor describes how to position the legend vertically.
  </DD>

<DT><I>top</I> or <I>bottom</I> </DT>
<DD>The anchor describes how to position the legend horizontally.
  </DD>

<DT><I>@x,y</I> </DT>
<DD>The anchor specifies how to position the legend relative to the
positioning point. For example, if <I>anchor</I> is <I>center</I> then the legend is centered
on the point; if <I>anchor</I> is <I>n</I> then the legend will be drawn such that the
top center point of the rectangular region occupied by the legend will
be at the positioning point. </DD>

<DT><I>plotarea</I> </DT>
<DD>The anchor specifies how to position
the legend relative to the plotting area. For example, if <I>anchor</I> is <I>center</I>
then the legend is centered in the plotting area; if <I>anchor</I> is <I>ne</I> then
the legend will be drawn such that occupies the upper right corner of the
plotting area. </DD>
</DL>
</blockquote>

<DL>

<DT><B>-background <I>color</I></B> </DT>
<DD>Sets the background color of the legend.
If <I>color</I> is <I>""</I>, the legend background with be transparent. </DD>

<DT><B>-borderwidth <I>pixels</I></B>
</DT>
<DD>Sets the width of the 3-D border around the outside edge of the legend (if
such border is being drawn; the <B>relief</B> option determines this). The default
is <I>2</I> pixels. </DD>

<DT><B>-font <I>fontName</I></B>  </DT>
<DD><I>FontName</I> specifies a font to use when drawing
the labels of each element into the legend.  The default is <I>*-Helvetica-Bold-R-Normal-*-12-120-*</I>.
</DD>

<DT><B>-foreground <I>color</I></B>  </DT>
<DD>Sets the foreground color of the text drawn for the element's
label. The default is <I>black</I>. </DD>

<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates whether the legend should
be displayed. If <I>boolean</I> is true, the legend will not be draw.  The default
is <I>no</I>. </DD>

<DT><B>-ipadx <I>pad</I></B>  </DT>
<DD>Sets the amount of internal padding to be added to the
width of each legend entry.  <I>Pad</I> can be a list of one or two screen distances.
 If <I>pad</I> has two elements, the left side of the legend entry is padded by
the first distance and the right side by the second.  If <I>pad</I> is just one
distance, both the left and right sides are padded evenly.  The default
is <I>2</I>. </DD>

<DT><B>-ipady <I>pad</I></B> </DT>
<DD>Sets an amount of internal padding to be added to the height
of each legend entry.  <I>Pad</I> can be a list of one or two screen distances.
 If <I>pad</I> has two elements, the top of the entry is padded by the first distance
and the bottom by the second.  If <I>pad</I> is just one distance, both the top
and bottom of the entry are padded evenly. The default is <I>2</I>. </DD>

<DT><B>-padx <I>pad</I></B> </DT>
<DD>Sets
the padding to the left and right exteriors of the legend. <I>Pad</I> can be a
list of one or two screen distances.  If <I>pad</I> has two elements, the left
side of the legend is padded by the first distance and the right side by
the second.  If <I>pad</I> has just one distance, both the left and right sides
are padded evenly.  The default is <I>4</I>. </DD>

<DT><B>-pady <I>pad</I></B> </DT>
<DD>Sets the padding above and
below the legend.  <I>Pad</I> can be a list of one or two screen distances.  If
<I>pad</I> has two elements, the area above the legend is padded by the first
distance and the area below by the second.  If <I>pad</I> is just one distance,
both the top and bottom areas are padded evenly.  The default is <I>0</I>. </DD>

<DT><B>-position
<I>pos</I></B> </DT>
<DD>Specifies where the legend is drawn. The <B>-anchor</B> option also affects
where the legend is positioned.  If <I>pos</I> is <I>left</I>, <I>left</I>, <I>top</I>, or <I>bottom</I>, the
legend is drawn in the specified margin.  If <I>pos</I> is <I>plotarea</I>, then the legend
is drawn inside the plotting area at a particular anchor.  If <I>pos</I> is in
the form "<I>@x,y</I>", where <I>x</I> and <I>y</I> are the window coordinates, the legend is
drawn in the plotting area at the specified coordinates.  The default is
<I>right</I>. </DD>

<DT><B>-raised <I>boolean</I></B> </DT>
<DD>Indicates whether the legend is above or below the
data elements.  This matters only if the legend is in the plotting area.
 If <I>boolean</I> is true, the legend will be drawn on top of any elements that
may overlap it. The default is <I>no</I>. </DD>

<DT><B>-relief <I>relief</I></B> </DT>
<DD>Specifies the 3-D effect
for the border around the legend. <I>Relief</I> specifies how the interior of the
legend should appear relative to the strip chart; for example, <I>raised</I> means
the legend should appear to protrude from the strip chart, relative to
the surface of the strip chart.  The default is <I>sunken</I>. </DD>
</DL>
<P>
Legend configuration
options may also be set by the <B>option</B> command.  The resource name and class
are <I>legend</I> and <I>Legend</I> respectively. <BR>
<CODE>option add *Stripchart.legend.Foreground blue<BR>
option add *Stripchart.Legend.Relief     raised<BR>
</blockquote>

<DL>

<DT></CODE><P><I>pathName <B>legend deactivate <I>pattern</I></B></I>... </DT>
<DD>Selects legend entries to be drawn using
the normal legend colors and relief.  All entries whose element names match
<I>pattern</I> are selected.  To be selected, the element name must match only
one <I>pattern</I>. </DD>

<DT><I>pathName <B>legend get <I>pos</I></B></I> </DT>
<DD>Returns the name of the element whose
entry is at the screen position <I>pos</I> in the legend.  <I>Pos</I> must be in the form
"<I>@x,y</I>", where <I>x</I> and <I>y</I> are window coordinates.  If the given coordinates
do not lie over a legend entry, <I>""</I> is returned. </DD>
</DL>

<H3><A NAME="sect13" HREF="#toc13">Pen Components</A></H3>
Pens define
attributes (both symbol and line style) for elements. Pens mirror the configuration
options of data elements that pertain to how symbols and lines are drawn.
 Data elements use pens to determine how they are drawn.  A data element
may use several pens at once.  In this case, the pen used for a particular
data point is determined from each element's weight vector (see the element's
<B>-weight</B> and <B>-style</B> options). <P>
One pen, called <I>activeLine</I>, is automatically
created. It's used as the default active pen for elements. So you can change
the active attributes for all elements by simply reconfiguring this pen.
<BR>
<CODE>.s pen configure "activeLine" -color green<BR>
</CODE><P>You can create and use any number of pens. To create a pen, invoke the pen
component and its create operation. <BR>
<CODE>.s pen create myPen<BR>
</CODE><P>You map pens to a data element using either the element's  <B>-pen</B> or <B>-activepen</B>
options. <BR>
<CODE>.s element create "line1" -xdata $x -ydata $tempData \<BR>
    -pen myPen<BR>
</CODE><P>An element can use several pens at once. This is done by specifying the
name of the pen in the element's style list (see the <B>-styles</B> option). <BR>
<CODE>.s element configure "line1" -styles { myPen 2.0 3.0 }<BR>
</CODE><P>This says that any data point with a weight between 2.0 and 3.0 is to be
drawn using the pen <I>myPen</I>.  All other points are drawn with the element's
default attributes. <P>
The following operations are available for pen components.
<P>

<DL>

<DT><I>pathName <B>pen <B>cget <I>penName <I>option</I></I></B></B></I> </DT>
<DD>Returns the current value of the option
given by <I>option</I> for <I>penName</I>.  <I>Option</I> may be any option described below for
the pen <B>configure</B> operation. </DD>

<DT><I>pathName <B>pen <B>configure <I>penName </I></B></B></I>?<I>option value</I>?...
</DT>
<DD>Queries or modifies the configuration options of <I>penName</I>.  If <I>option</I> isn't
specified, a list describing the current options for <I>penName</I> is returned.
 If <I>option</I> is specified, but not <I>value</I>, then a list describing <I>option</I> is
returned.  If one or more <I>option</I> and <I>value</I> pairs are specified, then for
each pair, the pen option <I>option</I> is set to <I>value</I>.   The following options
are valid for pens. <blockquote></DD>

<DT><B>-color <I>color</I></B>  </DT>
<DD>Sets the color of the traces connecting
the data points.   </DD>

<DT><B>-dashes <I>dashList</I></B> </DT>
<DD>Sets the dash style of element line. <I>DashList</I>
is a list of up to 11 numbers that alternately represent the lengths of
the dashes and gaps on the element line.  Each number must be between 1
and 255.  If <I>dashList</I> is <I>""</I>, the lines will be solid. </DD>

<DT><B>-fill <I>color</I></B>  </DT>
<DD>Sets the
interior color of symbols.  If <I>color</I> is <I>""</I>, then the interior of the symbol
is transparent.  If <I>color</I> is <I>defcolor</I>, then the color will be the same as
the <B>-color</B> option.  The default is <I>defcolor</I>. </DD>

<DT><B>-linewidth <I>pixels</I></B>  </DT>
<DD>Sets the width
of the connecting lines between data points.  If <I>pixels</I> is <I>0</I>, no connecting
lines will be drawn between symbols.  The default is <I>0</I>. </DD>

<DT><B>-offdash <I>color</I></B> </DT>
<DD>Sets
the color of the stripes when traces are dashed (see the <B>-dashes</B> option).
 If <I>color</I> is <I>""</I>, then the "off" pixels will represent gaps instead of stripes.
 If <I>color</I> is <I>defcolor</I>, then the color will be the same as the <B>-color</B> option.
 The default is <I>defcolor</I>. </DD>

<DT><B>-outline <I>color</I></B>  </DT>
<DD>Sets the color or the outline around
each symbol.  If <I>color</I> is <I>""</I>, then no outline is drawn. If <I>color</I> is <I>defcolor</I>,
then the color will be the same as the <B>-color</B> option.  The default is <I>defcolor</I>.
</DD>

<DT><B>-outlinewidth <I>pixels</I></B>  </DT>
<DD>Sets the width of the outline bordering each symbol.
 If <I>pixels</I> is <I>0</I>, no outline will be drawn. The default is <I>1</I>. </DD>

<DT><B>-pixels <I>pixels</I></B>
</DT>
<DD>Sets the size of symbols.  If <I>pixels</I> is <I>0</I>, no symbols will be drawn.  The
default is <I>0.125i</I>. </DD>

<DT><B>-symbol <I>symbol</I></B>  </DT>
<DD>Specifies the symbol for data points.  <I>Symbol</I>
can be either <I>square</I>, <I>circle</I>, <I>diamond</I>, <I>plus</I>, <I>cross</I>, <I>splus</I>, <I>scross</I>, <I>triangle</I>,
<I>""</I> (where no symbol is drawn), or a bitmap.  Bitmaps are specified as "<I>source</I>
?<I>mask</I>?", where <I>source</I> is the name of the bitmap, and <I>mask</I> is the bitmap's
optional mask.  The default is <I>circle</I>. </DD>

<DT><B>-type <I>elemType</I></B>  </DT>
<DD>Specifies the type
of element the pen is to be used with. This option should only be employed
when creating the pen.  This is for those that wish to mix different types
of elements (bars and lines) on the same graph.  The default type is "line".
</DD>
</DL>
<P>
Pen configuration options may be also be set by the <B>option</B> command.  The
resource class is <I>Pen</I>.  The resource names are the names of the pens. <BR>
<CODE>option add *Stripchart.Pen.Color  blue<BR>
option add *Stripchart.activeLine.color  green<BR>
</blockquote>

<DL>

<DT></CODE><P><I>pathName <B>pen <B>create <I>penName </I></B></B></I>?<I>option value</I>?... </DT>
<DD>Creates a new pen by the name
<I>penName</I>.  No pen by the same name can already exist. <I>Option</I> and <I>value</I> are
described  in above in the pen <B>configure</B> operation. </DD>

<DT><I>pathName <B>pen <B>delete
</B></B></I>?<I>penName</I>?... </DT>
<DD>Deletes the named pens. A pen is not really deleted until it is
not longer in use, so it's safe to delete pens mapped to elements. </DD>

<DT><I>pathName
<B>pen names </B></I>?<I>pattern</I>?... </DT>
<DD>Returns a list of pens matching zero or more patterns.
 If no <I>pattern</I> argument is give, the names of all pens are returned. </DD>
</DL>

<H3><A NAME="sect14" HREF="#toc14">PostScript
Component</A></H3>
The strip chart can generate encapsulated PostScript output.  There
are several configuration options you can specify to control how the plot
is generated.  You can change the page dimensions and borders.  The plot
itself can be scaled, centered, or rotated to landscape.  The PostScript
output can be written directly to a file or returned through the interpreter.
<P>
The following postscript operations are available. 
<DL>

<DT><I>pathName <B>postscript cget
<I>option</I></B></I>  </DT>
<DD>Returns the current value of the postscript option given by <I>option</I>.
 <I>Option</I> may be any option described below for the postscript <B>configure</B>
operation. </DD>

<DT><I>pathName <B>postscript configure </B></I>?<I>option value</I>?... </DT>
<DD>Queries or modifies
the configuration options for PostScript generation.  If <I>option</I> isn't specified,
a list describing  the current postscript options for <I>pathName</I> is returned.
 If <I>option</I> is specified, but not <I>value</I>, then a list describing <I>option</I> is
returned.  If one or more <I>option</I> and <I>value</I> pairs are specified, then for
each pair, the postscript option <I>option</I> is set to <I>value</I>.  The following
postscript options are available. <blockquote></DD>

<DT><B>-center <I>boolean</I></B> </DT>
<DD>Indicates whether the plot
should be centered on the PostScript page.  If <I>boolean</I> is false, the plot
will be placed in the upper left corner of the page.  The default is <I>1</I>. </DD>

<DT><B>-colormap
<I>varName</I></B> </DT>
<DD><I>VarName</I> must be the name of a global array variable that specifies
a color mapping from the X color name to PostScript.  Each element of <I>varName</I>
must consist of PostScript code to set a particular color value (e.g. ``<I>1.0
1.0 0.0 setrgbcolor</I>'').  When outputting color information in PostScript, the
array variable <I>varName</I>  is checked to see if an element of the name of
the color exists. If so,  it uses the value of the element as the PostScript
command to set the color.  If this option hasn't been specified, or if there
isn't an entry in <I>varName</I> for a given color, then it uses the red, green,
and blue intensities from the X color. </DD>

<DT><B>-colormode <I>mode</I></B> </DT>
<DD>Specifies how to output
color information.  <I>Mode</I> must be either <I>color</I> (for full color output), <I>gray</I>
(convert all colors to their gray-scale equivalents) or <I>mono</I> (convert foreground
colors to black and background colors to white).  The default mode is <I>color</I>.
 </DD>

<DT><B>-fontmap <I>varName</I></B> </DT>
<DD><I>VarName</I> must be the name of a global array variable that
specifies a font mapping from the X font name to PostScript.  Each element
of <I>varName</I> must consist of a Tcl list with one or two elements, which are
the name and point size of a PostScript font. When outputting PostScript
commands for a particular font, the  array variable <I>varName</I> is checked
to see an element of the specified  font exists.  If there is such an element,
then the font information contained in that element is used in the PostScript
output.  (If the point size is omitted from the list, the point size of
the X font is used).  Otherwise the X font is examined in an attempt to
guess what PostScript font to use.  This works only for fonts whose foundry
property is <I>Adobe</I> (such as Times, Helvetica, Courier, etc.).  If all of this
fails then the font defaults to <I>Helvetica-Bold</I>. </DD>

<DT><B>-decorations <I>boolean</I></B> </DT>
<DD>Indicates
if PostScript commands to generate color backgrounds and 3-D borders should
be output.  If <I>boolean</I> is false, the background will  be white and no 3-D
borders will be generated. The default is <I>1</I>. </DD>

<DT><B>-height <I>pixels</I></B> </DT>
<DD>Sets the height
of the plot.  This lets you plot the stripchart with a height different
from the one displayed on the screen.  If <I>pixels</I> is 0, the height is the
same as the displayed height. The default is <I>0</I>. </DD>

<DT><B>-landscape <I>boolean</I></B> </DT>
<DD>If <I>boolean</I>
is true, this specifies the printed area is to be rotated 90 degrees.  In
non-rotated output the X-axis of the printed area runs along the short dimension
of the page (``portrait'' orientation); in rotated output the X-axis runs along
the long dimension of the page (``landscape'' orientation).  Defaults to <I>0</I>. </DD>

<DT><B>-maxpect
<I>boolean</I></B> </DT>
<DD>Indicates to scale the the plot so that it fills the PostScript
page. The aspect ratio of the strip chart is still retained.  The default
is <I>0</I>. </DD>

<DT><B>-padx <I>pad</I></B> </DT>
<DD>Sets the horizontal padding for the left and right page borders.
 The borders are exterior to the plot.  <I>Pad</I> can be a list of one or two
screen distances.  If <I>pad</I> has two elements, the left border is padded by
the first distance and the right border by the second.  If <I>pad</I> has just
one distance, both the left and right borders are padded evenly.  The default
is <I>1i</I>. </DD>

<DT><B>-pady <I>pad</I></B>  </DT>
<DD>Sets the vertical padding for the top and bottom page borders.
The borders are exterior to the plot.  <I>Pad</I> can be a list of one or two screen
distances.  If <I>pad</I> has two elements, the top border is padded by the first
distance and the bottom border by the second.  If <I>pad</I> has just one distance,
both the top and bottom borders are padded evenly.  The default is <I>1i</I>. </DD>

<DT><B>-paperheight
<I>pixels</I></B> </DT>
<DD>Sets the height of the postscript page.  This can be used to select
between different page sizes (letter, A4, etc).  The default height is <I>11.0i</I>.
</DD>

<DT><B>-paperwidth <I>pixels</I></B> </DT>
<DD>Sets the width of the postscript page.  This can be used
to select between different page sizes (letter, A4, etc).  The default width
is <I>8.5i</I>. </DD>

<DT><B>-width <I>pixels</I></B> </DT>
<DD>Sets the width of the plot.  This lets you plot the
strip chart with a width different from the one drawn on the screen.  If
<I>pixels</I> is 0, the width is the same as the widget's width.  The default is
<I>0</I>. </DD>
</DL>
<P>
Postscript configuration options may be also be set by the <B>option</B> command.
 The resource name and class are <I>postscript</I> and <I>Postscript</I> respectively.
<BR>
<CODE>option add *Stripchart.postscript.Decorations false<BR>
option add *Stripchart.Postscript.Landscape   true<BR>
</blockquote>

<DL>

<DT></CODE><P><I>pathName <B>postscript output </B></I>?<I>fileName</I>? ?<I>option value</I>?... </DT>
<DD>Outputs a file of
encapsulated PostScript.  If a <I>fileName</I> argument isn't present, the command
returns the PostScript. If any <I>option-value</I> pairs are present, they set configuration
options controlling how the PostScript is generated. <I>Option</I> and <I>value</I> can
be anything accepted by the postscript <B>configure</B> operation above. </DD>
</DL>

<H3><A NAME="sect15" HREF="#toc15">Marker
Components</A></H3>
Markers are simple drawing procedures used to annotate or highlight
areas of the strip chart.  Markers have various types: text strings, bitmaps,
images, connected lines, windows, or polygons.  They can be associated with
a particular element, so that when the element is hidden or un-hidden, so
is the marker.  By default, markers are the last items drawn, so that data
elements will appear in behind them.  You can change this by configuring
the <B>-under</B> option. <P>
Markers, in contrast to elements, don't affect the scaling
of the coordinate axes.  They can also have <I>elastic</I> coordinates (specified
by <I>-Inf</I> and <I>Inf</I> respectively) that translate into the minimum or maximum
limit of the axis.  For example, you can place a marker so it always remains
in the lower left corner of the plotting area, by using the coordinates
<I>-Inf</I>,<I>-Inf</I>. <P>
The following operations are available for markers. 
<DL>

<DT><I>pathName <B>marker
after <I>markerId</I></B></I> ?<I>afterId</I>? </DT>
<DD>Changes the order of the markers, drawing the
first marker after the second.  If no second <I>afterId</I> argument is specified,
the marker is placed at the end of the display list.  This command can be
used to control how markers are displayed since markers are drawn in the
order of this display list. </DD>

<DT><I>pathName <B>marker before <I>markerId</I></B></I> ?<I>beforeId</I>? </DT>
<DD>Changes
the order of the markers, drawing the first marker before the second.  If
no second <I>beforeId</I> argument is specified, the marker is placed at the beginning
of the display list. This command can be used to control how markers are
displayed since markers are drawn in the order of this display list. </DD>

<DT><I>pathName
<B>marker cget <I>option</I></B></I> </DT>
<DD>Returns the current value of the marker configuration
option given by <I>option</I>.  <I>Option</I> may be any option described below in the
<B>configure</B> operation. </DD>

<DT><I>pathName <B>marker configure <I>markerId</I></B></I> ?<I>option value</I>?... </DT>
<DD>Queries
or modifies the configuration options for markers.  If <I>option</I> isn't specified,
a list describing the current options for <I>markerId</I> is returned.  If <I>option</I>
is specified, but not <I>value</I>, then a list describing <I>option</I> is returned.
If one or more <I>option</I> and <I>value</I> pairs are specified, then for each pair,
the marker option <I>option</I> is set to <I>value</I>. <P>
The following options are valid
for all markers. Each type of marker also has its own type-specific options.
  They are described in the sections below. <blockquote></DD>

<DT><B>-coords <I>coordList</I></B> </DT>
<DD>Specifies the
coordinates of the marker.  <I>CoordList</I> is  a list of graph coordinates.  The
number of coordinates required is dependent on the type of marker.  Text,
image, and window markers need only two coordinates (an X-Y coordinate).
  Bitmap markers can take either two or four coordinates (if four, they
represent the corners of the bitmap). Line markers need at least four coordinates,
polygons at least six. If <I>coordList</I> is <I>""</I>, the marker will not be displayed.
The default is <I>""</I>. </DD>

<DT><B>-element <I>elemName</I></B> </DT>
<DD>Links the marker with the element <I>elemName</I>.
 The marker is drawn only if the element is also currently displayed (see
the element's <B>show</B> operation).  If <I>elemName</I> is <I>""</I>, the marker is always drawn.
 The default is <I>""</I>. </DD>

<DT><B>-hide <I>boolean</I></B>  </DT>
<DD>Indicates whether the marker is drawn.
If <I>boolean</I> is true, the marker is not drawn.  The default is <I>no</I>. </DD>

<DT><B>-mapx <I>xAxis</I></B>
 </DT>
<DD>Specifies the X-axis to map the marker's X-coordinates onto. <I>XAxis</I> must the
name of an axis.  The default is <I>x</I>. </DD>

<DT><B>-mapy <I>yAxis</I></B> </DT>
<DD>Specifies the Y-axis to map
the marker's Y-coordinates onto. <I>YAxis</I> must the name of an axis.  The default
is <I>y</I>. </DD>

<DT><B>-name <I>markerId</I></B> </DT>
<DD>Changes the identifier for the marker.  The identifier
<I>markerId</I>  can not already be used by another marker.  If this option isn't
specified, the marker's name is uniquely generated. </DD>

<DT><B>-under <I>boolean</I></B> </DT>
<DD>Indicates
whether the marker is drawn below/above data elements.  If <I>boolean</I> is true,
the marker is be drawn underneath the data element symbols and lines.  Otherwise,
the marker is drawn on top of the element.  The default is <I>0</I>. </DD>

<DT><B>-xoffset <I>pixels</I></B>
</DT>
<DD>Specifies a screen distance to offset the marker horizontally.  <I>Pixels</I> is
a valid screen distance, such as <I>2</I> or <I>1.2i</I>. The default is <I>0</I>. </DD>

<DT><B>-yoffset <I>pixels</I></B>
</DT>
<DD>Specifies a screen distance to offset the markers vertically. <I>Pixels</I> is
a valid screen distance, such as <I>2</I> or <I>1.2i</I>. The default is <I>0</I>. </DD>
</DL>
<P>
Marker configuration
options may also be set by the <B>option</B> command. The resource class is either
<I>BitmapMarker</I>,  <I>ImageMarker</I>,  <I>LineMarker</I>, <I>PolygonMarker</I>, <I>TextMarker</I>, or
<I>WindowMarker</I>, depending on the type of marker.  The resource name is the
name of the marker. <BR>
<CODE>option add *Stripchart.TextMarker.Foreground white<BR>
option add *Stripchart.BitmapMarker.Foreground white<BR>
option add *Stripchart.m1.Background     blue<BR>
</blockquote>

<DL>

<DT></CODE><P><I>pathName <B>marker create <I>type</I></B></I> ?<I>option value</I>?... </DT>
<DD>Creates a marker of the selected
type. <I>Type</I> may be either <I>text</I>, <I>line</I>, <I>bitmap</I>, <I>image</I>, <I>polygon</I>, or <I>window</I>. 
This command returns the marker identifier,  used as the <I>markerId</I> argument
in the other marker-related commands.  If the <B>-name</B> option is used, this overrides
the normal marker identifier.  If the name provided is already used for
another marker, the new marker will replace the old. </DD>

<DT><I>pathName <B>marker delete</B></I>
?<I>name</I>?... </DT>
<DD>Removes one of more markers.  The graph will automatically be redrawn
without the marker..   </DD>

<DT><I>pathName <B>marker exists <I>markerId</I></B></I>  </DT>
<DD>Returns <I>1</I> if the
marker <I>markerId</I> exists and <I>0</I> otherwise. </DD>

<DT><I>pathName <B>marker names</B></I> ?<I>pattern</I>?
  </DT>
<DD>Returns the names of all the markers that currently exist.  If <I>pattern</I>
is supplied, only those markers whose names match it will be returned. </DD>

<DT><I>pathName
<B>marker type <I>markerId</I></B></I>  </DT>
<DD>Returns the type of the marker given by <I>markerId</I>,
such as <I>line</I> or <I>text</I>.  If <I>markerId</I> is not a valid a marker identifier, <I>""</I>
is returned. </DD>
</DL>

<H3><A NAME="sect16" HREF="#toc16">Bitmap Markers</A></H3>
A bitmap marker displays a bitmap.  The size of
the bitmap is controlled by the number of coordinates specified.  If two
coordinates, they specify the position of the top-left corner of the bitmap.
 The bitmap retains its normal width and height.  If four coordinates, the
first and second pairs of coordinates represent the corners of the bitmap.
 The bitmap will be stretched or reduced as necessary to fit into the bounding
rectangle. <P>
Bitmap markers are created with the marker's <B>create</B> operation
in the form: <BR>
<P>
<CODE><I>pathName <B>marker create bitmap </B></I>?<I>option value</I>?...<BR>
</CODE><P>There may be many <I>option</I>-<I>value</I> pairs, each  sets a configuration options
for the marker.  These same <I>option</I>-<I>value</I> pairs may be used with the marker's
<B>configure</B> operation. <P>
The following options are specific to bitmap markers:

<DL>

<DT><B>-background <I>color</I></B> </DT>
<DD>Sets the background color of the bitmap.  If <I>color</I> is <I>""</I>,
the background color will be transparent.  The default background color
is <I>white</I>. </DD>

<DT><B>-bitmap <I>bitmap</I></B> </DT>
<DD>Specifies the bitmap to be displayed.  If <I>bitmap</I>
is <I>""</I>, the marker will not be displayed.  The default is <I>""</I>. </DD>

<DT><B>-foreground <I>color</I></B>
 </DT>
<DD>Sets the foreground color of the bitmap.  The default foreground color
is <I>black</I>. </DD>

<DT><B>-mask <I>mask</I></B> </DT>
<DD>Specifies a mask for the bitmap to be displayed. This
mask is a bitmap itself, denoting the pixels that are transparent.  If <I>mask</I>
is <I>""</I>, all pixels of the bitmap will be drawn.  The default is <I>""</I>. </DD>

<DT><B>-rotate
<I>theta</I></B> </DT>
<DD>Sets the rotation of the bitmap.  <I>Theta</I> is a real number representing
the angle of rotation in degrees.  The marker is first rotated and then
placed according to its anchor position.  The default rotation is <I>0.0</I>. </DD>
</DL>

<H3><A NAME="sect17" HREF="#toc17">Image
Markers</A></H3>
A image marker displays an image.  Image markers are created with
the marker's <B>create</B> operation in the form: <BR>
<P>
<CODE><I>pathName <B>marker create image </B></I>?<I>option value</I>?...<BR>
</CODE><P>There may be many <I>option</I>-<I>value</I> pairs, each sets a configuration option for
the marker.  These same <I>option</I>-<I>value</I> pairs may be used with the marker's <B>configure</B>
operation. <P>
The following options are specific to image markers: 
<DL>

<DT><B>-anchor <I>anchor</I></B>
</DT>
<DD><I>Anchor</I> tells how to position the image relative to the positioning point
for the image. For example, if <I>anchor</I> is <I>center</I> then the image is centered
on the point;  if <I>anchor</I> is <I>n</I> then the image will be drawn such that the
top center point of the rectangular region occupied by the image will be
at the positioning point. This option defaults to <I>center</I>. </DD>

<DT><B>-image <I>image</I></B> </DT>
<DD>Specifies
the image to be drawn. If <I>image</I> is <I>""</I>, the marker will not be drawn.  The
default is <I>""</I>. </DD>
</DL>

<H3><A NAME="sect18" HREF="#toc18">Line Markers</A></H3>
A line marker displays one or more connected
line segments. Line markers are created with marker's <B>create</B> operation in
the form: <BR>
<P>
<CODE><I>pathName <B>marker create line </B></I>?<I>option value</I>?...<BR>
</CODE><P>There may be many <I>option</I>-<I>value</I> pairs, each sets a configuration option for
the marker.  These same <I>option</I>-<I>value</I> pairs may be used with the marker's <B>configure</B>
operation. <P>
The following options are specific to line markers: 
<DL>

<DT><B>-background
<I>color</I></B> </DT>
<DD>Sets the background color of the line. The option is affects the line
color only when the <B>-stipple</B> option  is set.   If this option isn't specified
then it defaults to <I>white</I>. </DD>

<DT><B>-dashes <I>dashList</I></B> </DT>
<DD>Sets the dash style of the line.
<I>DashList</I> is a list of up to 11 numbers that alternately represent the lengths
of the dashes and gaps on the line.  Each number must be between 1 and 255.
 If <I>dashList</I> is <I>""</I>, the marker line will be solid. </DD>

<DT><B>-foreground <I>color</I></B> </DT>
<DD>Sets
the foreground color.  The default foreground color is <I>black</I>. </DD>

<DT><B>-linewidth <I>pixels</I></B>
</DT>
<DD>Sets the width of the lines. The default width is <I>0</I>. </DD>

<DT><B>-stipple <I>bitmap</I></B> </DT>
<DD>Specifies
a stipple pattern used to draw the line, rather than a solid line. <I>Bitmap</I>
specifies a bitmap to use as the stipple pattern.  If <I>bitmap</I> is <I>""</I>, then
the line is drawn in a solid fashion. The default is <I>""</I>. </DD>
</DL>

<H3><A NAME="sect19" HREF="#toc19">Polygon Markers</A></H3>
A
polygon marker displays a closed region described as two or more connected
line segments.  It is assumed the first and last points are connected.  Polygon
markers are created using the marker <B>create</B> operation in the form: <BR>
<P>
<CODE><I>pathName <B>marker create polygon </B></I>?<I>option value</I>?...<BR>
</CODE><P>There may be many <I>option</I>-<I>value</I> pairs, each sets a configuration option for
the marker.  These same <I>option</I>-<I>value</I> pairs may be used with the <B>marker configure</B>
command to change the marker's configuration. The following options are supported
for polygon markers: 
<DL>

<DT><B>-dashes <I>dashList</I></B> </DT>
<DD>Sets the dash style of the outline
of the polygon. <I>DashList</I> is a list of up to 11 numbers that alternately
represent the lengths of the dashes and gaps on the outline.  Each number
must be between 1 and 255. If <I>dashList</I> is <I>""</I>, the outline will be a solid
line. </DD>

<DT><B>-fill <I>color</I></B> </DT>
<DD>Sets the fill color of the polygon.  If <I>color</I> is <I>""</I>, then
the interior of the polygon is transparent. The default is <I>white</I>. </DD>

<DT><B>-linewidth
<I>pixels</I></B> </DT>
<DD>Sets the width of the outline of the polygon. If <I>pixels</I> is zero,
 no outline is drawn. The default is <I>0</I>. </DD>

<DT><B>-outline <I>color</I></B> </DT>
<DD>Sets the color of the
outline of the polygon.  If the polygon is stippled (see the <B>-stipple</B> option),
then this represents the foreground color of the stipple.  The default is
<I>black</I>. </DD>

<DT><B>-stipple <I>bitmap</I></B> </DT>
<DD>Specifies that the polygon should be drawn with a
stippled pattern rather than a solid color. <I>Bitmap</I> specifies a bitmap to
use as the stipple pattern.  If <I>bitmap</I> is <I>""</I>, then the polygon is filled
with a solid color (if the <B>-fill</B> option is set).  The default is <I>""</I>. </DD>
</DL>

<H3><A NAME="sect20" HREF="#toc20">Text
Markers</A></H3>
A text marker displays a string of characters on one or more lines
of text.  Embedded newlines cause line breaks.  They may be used to annotate
regions of the strip chart.  Text markers are created with the <B>create</B> operation
in the form: <BR>
<P>
<CODE><I>pathName <B>marker create text </B></I>?<I>option value</I>?...<BR>
</CODE><P>There may be many <I>option</I>-<I>value</I> pairs,  each sets a configuration option
for the text marker.   These same <I>option</I>-<I>value</I> pairs may be used with the
 marker's <B>configure</B> operation.   <P>
The following options are specific to text
markers: 
<DL>

<DT><B>-anchor <I>anchor</I></B> </DT>
<DD><I>Anchor</I> tells how to position the text relative to
the positioning point for the text. For example, if <I>anchor</I> is <I>center</I> then
the text is centered on the point; if <I>anchor</I> is <I>n</I> then the text will be
drawn such that the top center point of the rectangular region occupied
by the text will be at the positioning point.  This default is <I>center</I>. </DD>

<DT><B>-background
<I>color</I></B> </DT>
<DD>Sets the background color of the text string.  If <I>color</I> is <I>""</I>, the
background will be transparent.  The default is <I>white</I>. </DD>

<DT><B>-font <I>fontName</I></B> </DT>
<DD>Specifies
the font of the text.  The default is <I>*-Helvetica-Bold-R-Normal-*-120-*</I>. </DD>

<DT><B>-foreground
<I>color</I></B> </DT>
<DD>Sets the foreground color of the text.  The default is <I>black</I>. </DD>

<DT><B>-justify
<I>justify</I></B> </DT>
<DD>Specifies how the text should be justified.  This matters only when
the marker contains more than one line of text. <I>Justify</I> must be <I>left</I>, <I>right</I>,
or <I>center</I>.  The default is <I>center</I>. </DD>

<DT><B>-padx <I>pad</I></B> </DT>
<DD>Sets the padding to the left
and right exteriors of the text. <I>Pad</I> can be a list of one or two screen
distances.  If <I>pad</I> has two elements, the left side of the text is padded
by the first distance and the right side by the second.  If <I>pad</I> has just
one distance, both the left and right sides are padded evenly.  The default
is <I>4</I>. </DD>

<DT><B>-pady <I>pad</I></B> </DT>
<DD>Sets the padding above and below the text.  <I>Pad</I> can be a list
of one or two screen distances.  If <I>pad</I> has two elements, the area above
the text is padded by the first distance and the area below by the second.
If <I>pad</I> is just one distance, both the top and bottom areas are padded evenly.
 The default is <I>4</I>. </DD>

<DT><B>-rotate <I>theta</I></B> </DT>
<DD>Specifies the number of degrees to rotate
the text.  <I>Theta</I> is a real number representing the angle of rotation.  The
marker is first rotated along its center and is then drawn according to
its anchor position. The default is <I>0.0</I>. </DD>

<DT><B>-text <I>text</I></B> </DT>
<DD>Specifies the text of the
marker.  The exact way the text is displayed may be affected by other options
such as <B>-anchor</B> or <B>-rotate</B>. </DD>
</DL>

<H3><A NAME="sect21" HREF="#toc21">Window Markers</A></H3>
A window marker displays a widget
at a given position. Window markers are created with the marker's <B>create</B>
operation in the form: <BR>
<P>
<CODE><I>pathName <B>marker create window </B></I>?<I>option value</I>?...<BR>
</CODE><P>There may be many <I>option</I>-<I>value</I> pairs, each sets a configuration option for
the marker.  These same <I>option</I>-<I>value</I> pairs may be used with the marker's <B>configure</B>
command. <P>
The following options are specific to window markers: 
<DL>

<DT><B>-anchor <I>anchor</I></B>
</DT>
<DD><I>Anchor</I> tells how to position the widget relative to the positioning point
for the widget. For example, if <I>anchor</I> is <I>center</I> then the widget is centered
on the point; if <I>anchor</I> is <I>n</I> then the widget will be displayed such that
the top center point of the rectangular region occupied by the widget will
be at the positioning point.  This option defaults to <I>center</I>. </DD>

<DT><B>-height <I>pixels</I></B>
</DT>
<DD>Specifies the height to assign to the marker's window.  If this option isn't
specified, or if it is specified as <I>""</I>, then the window is given whatever
height the widget requests internally. </DD>

<DT><B>-width <I>pixels</I></B> </DT>
<DD>Specifies the width
to assign to the marker's window.  If this option isn't specified, or if it
is specified as <I>""</I>, then the window is given whatever width the widget
requests internally. </DD>

<DT><B>-window <I>pathName</I></B> </DT>
<DD>Specifies the widget to be managed.
 <I>PathName</I> must be a child of the <B>stripchart</B> widget. </DD>
</DL>

<H2><A NAME="sect22" HREF="#toc22">Graph Component Bindings</A></H2>
Specific
stripchart components, such as elements, markers and legend entries, can
have a command trigger when event occurs in them, much like canvas items
in Tk's canvas widget.  Not all event sequences are valid.  The only binding
events that may be specified are those related to the mouse and keyboard
(such as <B>Enter</B>, <B>Leave</B>, <B>ButtonPress</B>, <B>Motion</B>, and <B>KeyPress</B>). <P>
Only one element
or marker can be picked during an event.  This means, that if the mouse
is directly over both an element and a marker, only the uppermost component
is selected.  This isn't true for legend entries.   Both a legend entry and
an element (or marker) binding commands  will be invoked if both items
are picked. <P>
It is possible for multiple bindings to match a particular event.
This could occur, for example, if one binding is associated with the element
name and another is associated with one of the element's tags (see the <B>-bindtags</B>
option).  When this occurs, all of the  matching bindings are invoked.  A
binding associated with the element name is invoked first, followed by
one binding for each of the element's  bindtags.  If there are multiple matching
bindings for a single tag,  then only the most specific binding is invoked.
 A continue command  in a binding script terminates that script, and a
break command  terminates that script and skips any remaining scripts for
the event,  just as for the bind command. <P>
The <B>-bindtagsR option for these
components controls addition tag names which can be matched.  Implicitly
elements and markers always have tags matching their names.  Setting the
value of the <B>-bindtags</B></B> option doesn't change this. 
<H2><A NAME="sect23" HREF="#toc23">C Language API</A></H2>
You can manipulate
data elements from the C language.  There may be situations where it is
too expensive to translate the data values from ASCII strings.  Or you might
want to read data in a special file format. <P>
Data can manipulated from the
C language using BLT vectors. You specify the x and y data coordinates of
an element as vectors and manipulate the vector from C.  The strip chart
will be redrawn automatically after the vectors are updated. <P>
From Tcl, create
the vectors and configure the element to use them. <BR>
<CODE>vector X Y<BR>
.s element configure line1 -xdata X -ydata Y<BR>
</CODE><P>To set data points from C, you pass the values as arrays of doubles using
the <B>Blt_ResetVector</B> call.  The vector is reset with the new data and at
the next idle point (when Tk re-enters its event loop), the strip chart
will be redrawn automatically. <BR>
<CODE>#include &lt;tcl.h&gt;<BR>
#include &lt;blt.h&gt;<BR>
<P>
register int i;<BR>
Blt_Vector *xVec, *yVec;<BR>
double x[50], y[50];<BR>
<P>
/* Get the BLT vectors "X" and "Y" (created above from Tcl) */<BR>
if ((Blt_GetVector(interp, "X", 50, &amp;xVec) != TCL_OK) ||<BR>
    (Blt_GetVector(interp, "Y", 50, &amp;yVec) != TCL_OK)) {<BR>
    return TCL_ERROR;<BR>
}<BR>
<P>
for (i = 0; i &lt; 50; i++) {<BR>
    x[i] = i * 0.02;<BR>
    y[i] = sin(x[i]);<BR>
}<tt>&#32;</tt>&nbsp;<tt>&#32;</tt>&nbsp;<BR>
<P>
/* Put the data into BLT vectors */<BR>
if ((Blt_ResetVector(xVec, x, 50, 50, TCL_VOLATILE) != TCL_OK) ||<BR>
    (Blt_ResetVector(yVec, y, 50, 50, TCL_VOLATILE) != TCL_OK)) {<BR>
   return TCL_ERROR;<BR>
}<BR>
</CODE><P>See the <B>vector</B> manual page for more details. 
<H2><A NAME="sect24" HREF="#toc24">Speed Tips</A></H2>
There may be cases
where the strip chart needs to be drawn and updated as quickly as possible.
 If drawing speed becomes a big problem, here are a few tips to speed up
displays. 
<UL>
&#183;<LI>Try to minimize the number of data points.  The more data points
the looked at, the more work the strip chart must do. </LI>&#183;<LI>If your data is generated
as floating point values, the time required to convert the data values
to and from ASCII strings can be significant, especially when there any
many data points.  You can avoid the redundant string-to-decimal conversions
using the C API to BLT vectors. </LI>&#183;<LI>Data elements without symbols are drawn
faster than with symbols. Set the data element's <B>-symbol</B> option to <I>none</I>.  If
you need to draw symbols, try using the simple symbols such as <I>splus</I> and
<I>scross</I>. </LI>&#183;<LI>Don't stipple or dash the element.  Solid lines are much faster. </LI>&#183;<LI>If
you update data elements frequently, try turning off the widget's <B>-bufferelements</B>
option.  When the strip chart is first displayed, it draws data elements
into an internal pixmap.  The pixmap acts as a cache, so that when the strip
chart needs to be redrawn again, and the data elements or coordinate axes
haven't changed, the pixmap is simply copied to the screen.  This is especially
useful when you are using markers to highlight points and regions on the
strip chart.  But if the strip chart is updated frequently, changing either
the element data or coordinate axes, the buffering becomes redundant. </LI>
</UL>

<H2><A NAME="sect25" HREF="#toc25">Limitations</A></H2>
Auto-scale
routines do not use requested min/max limits as boundaries when the axis
is logarithmically scaled. <P>
The PostScript output generated for polygons
with more than 1500 points may exceed the limits of some printers (See
PostScript Language Reference Manual, page 568).  The work-around is to break
the polygon into separate pieces. 
<H2><A NAME="sect26" HREF="#toc26">Future Incompatibility</A></H2>
The <B>-mapped</B> options
are obsoleted and will be removed.  You can achieve the same results using
the <B>-hide</B> option instead. <BR>
<CODE># Works for now.<BR>
.s legend configure -mapped no<BR>
<P>
# Instead use this.<BR>
.s legend configure -hide yes    <BR>

<H2><A NAME="sect27" HREF="#toc27"></CODE><P>Keywords</A></H2>
stripchart, graph, widget <P>

<HR><P>
<A NAME="toc"><B>Table of Contents</B></A><P>
<UL>
<LI><A NAME="toc0" HREF="#sect0">Name</A></LI>
<LI><A NAME="toc1" HREF="#sect1">Synopsis</A></LI>
<LI><A NAME="toc2" HREF="#sect2">Description</A></LI>
<LI><A NAME="toc3" HREF="#sect3">Introduction</A></LI>
<LI><A NAME="toc4" HREF="#sect4">Syntax</A></LI>
<LI><A NAME="toc5" HREF="#sect5">Example</A></LI>
<LI><A NAME="toc6" HREF="#sect6">Stripchart Operations</A></LI>
<LI><A NAME="toc7" HREF="#sect7">Stripchart Components</A></LI>
<UL>
<LI><A NAME="toc8" HREF="#sect8">Axis Components</A></LI>
<LI><A NAME="toc9" HREF="#sect9">Crosshairs Component</A></LI>
<LI><A NAME="toc10" HREF="#sect10">Element Components</A></LI>
<LI><A NAME="toc11" HREF="#sect11">Grid Component</A></LI>
<LI><A NAME="toc12" HREF="#sect12">Legend Component</A></LI>
<LI><A NAME="toc13" HREF="#sect13">Pen Components</A></LI>
<LI><A NAME="toc14" HREF="#sect14">PostScript Component</A></LI>
<LI><A NAME="toc15" HREF="#sect15">Marker Components</A></LI>
<LI><A NAME="toc16" HREF="#sect16">Bitmap Markers</A></LI>
<LI><A NAME="toc17" HREF="#sect17">Image Markers</A></LI>
<LI><A NAME="toc18" HREF="#sect18">Line Markers</A></LI>
<LI><A NAME="toc19" HREF="#sect19">Polygon Markers</A></LI>
<LI><A NAME="toc20" HREF="#sect20">Text Markers</A></LI>
<LI><A NAME="toc21" HREF="#sect21">Window Markers</A></LI>
</UL>
<LI><A NAME="toc22" HREF="#sect22">Graph Component Bindings</A></LI>
<LI><A NAME="toc23" HREF="#sect23">C Language API</A></LI>
<LI><A NAME="toc24" HREF="#sect24">Speed Tips</A></LI>
<LI><A NAME="toc25" HREF="#sect25">Limitations</A></LI>
<LI><A NAME="toc26" HREF="#sect26">Future Incompatibility</A></LI>
<LI><A NAME="toc27" HREF="#sect27">Keywords</A></LI>
</UL>
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