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//--------------------------------------------------------------------------
// $Id: x16.java 12372 2013-06-06 21:44:33Z andrewross $
//--------------------------------------------------------------------------

//--------------------------------------------------------------------------
// Copyright (C) 2001  Geoffrey Furnish
// Copyright (C) 2002  Alan W. Irwin
// Copyright (C) 2004  Andrew Ross
//
// This file is part of PLplot.
//
// PLplot is free software; you can redistribute it and/or modify
// it under the terms of the GNU Library General Public License as published by
// the Free Software Foundation; version 2 of the License.
//
// PLplot is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public License
// along with PLplot; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
//--------------------------------------------------------------------------

//--------------------------------------------------------------------------
// Implementation of PLplot example 16 in Java.
//--------------------------------------------------------------------------

package plplot.examples;

import plplot.core.*;
import static plplot.core.plplotjavacConstants.*;

import java.lang.Math;

class x16 {
    // number of shade levels, x data points, y data points, and perimeter points.
    static final int NSHADES      = 20;
    static final int XPTS         = 35;
    static final int YPTS         = 46;
    static final int PERIMETERPTS = 100;
    static final int NUM_AXES     = 1;
    static final int NUM_LABELS   = 1;

    // calculated constants and array that depends on them
    static final double XSPA = 2. / ( XPTS - 1 );
    static final double YSPA = 2. / ( YPTS - 1 );
    final double        tr[] = { XSPA, 0.0, -1.0, 0.0, YSPA, -1.0 };

    PLStream            pls = new PLStream();

    double fmin, fmax;

    // Compute min and max value of a 2-d array.

    void f2mnmx( double[][] f, int nx, int ny )
    {
        fmax = f[0][0];
        fmin = fmax;

        for ( int i = 0; i < nx; i++ )
            for ( int j = 0; j < ny; j++ )
            {
                if ( f[i][j] < fmin ) fmin = f[i][j];
                if ( f[i][j] > fmax ) fmax = f[i][j];
            }
    }

    // Does a variety of shade plots with continuous (cmap1) colours

    public static void main( String[] args )
    {
        new x16( args );
    }

    public x16( String[] args )
    {
        int    i, j;
        double x, y, argx, argy, distort, r, t, zmin, zmax;
        double[] px     = new double[PERIMETERPTS];
        double[] py     = new double[PERIMETERPTS];
        double[][] xg0  = new double[XPTS][YPTS];
        double[][] yg0  = new double[XPTS][YPTS];
        double[][] xg1  = new double[XPTS][YPTS];
        double[][] yg1  = new double[XPTS][YPTS];
        double[][] z    = new double[XPTS][YPTS];
        double[][] w    = new double[XPTS][YPTS];
        double[][] xg2  = new double[XPTS][YPTS];
        double[][] yg2  = new double[XPTS][YPTS];
        double[] clevel = new double[NSHADES];
        double[] shedge = new double[NSHADES + 1];
        final int    cont_color = 0;
        final double fill_width = 2., cont_width = 0.;
        double[] colorbar_width  = new double[1];
        double[] colorbar_height = new double[1];

        int n_axis_opts = NUM_AXES;
        int[] num_values  = new int[NUM_AXES];
        double[][] values = new double[NUM_AXES][NSHADES + 1];
        String axis_opts[]     = { "bcvtm" };
        double axis_ticks[]    = { 0.0 };
        int    axis_subticks[] = { 0 };
        double filler_values[] = { 0.0, 1.0 };

        int    n_labels     = NUM_LABELS;
        int    label_opts[] = { PL_COLORBAR_LABEL_BOTTOM };
        String labels[]     = { "Magnitude" };

        // Parse and process command line arguments.
        pls.parseopts( args, PL_PARSE_FULL | PL_PARSE_NOPROGRAM );

        // Load colour palettes
        pls.spal0( "cmap0_black_on_white.pal" );
        pls.spal1( "cmap1_gray.pal", true );
        // Reduce colors in cmap 0 so that cmap 1 is useful on a
        //16-color display
        pls.scmap0n( 3 );

        //Initialize plplot

        pls.init();
        // Set up data array

        for ( i = 0; i < XPTS; i++ )
        {
            x = (double) ( i - ( XPTS / 2 ) ) / (double) ( XPTS / 2 );
            for ( j = 0; j < YPTS; j++ )
            {
                y = (double) ( j - ( YPTS / 2 ) ) / (double) ( YPTS / 2 ) - 1.0;

                z[i][j] = -Math.sin( 7. * x ) * Math.cos( 7. * y ) + x * x - y * y;
                w[i][j] = -Math.cos( 7. * x ) * Math.sin( 7. * y ) + 2 * x * y;
            }
        }

        f2mnmx( z, XPTS, YPTS );
        zmin = fmin;
        zmax = fmax;

        for ( i = 0; i < NSHADES; i++ )
            clevel[i] = zmin + ( zmax - zmin ) * ( i + 0.5 ) / NSHADES;

        for ( i = 0; i < NSHADES + 1; i++ )
            shedge[i] = zmin + ( zmax - zmin ) * i / NSHADES;

        for ( i = 0; i < XPTS; i++ )
        {
            for ( j = 0; j < YPTS; j++ )
            {
                // Replacement for mypltr of x16c.c
                x = tr[0] * i + tr[1] * j + tr[2];
                y = tr[3] * i + tr[4] * j + tr[5];

                argx    = x * Math.PI / 2;
                argy    = y * Math.PI / 2;
                distort = 0.4;

                // Note xg0 ==> yg1 are one-dimensional because of arrangement of
                //zeros in the final tr definition above.  However, for now
                //we are using raw interface here so must nominally treat them
                //as two-dimensional.
                xg0[i][j] = x;
                yg0[i][j] = y;

                xg1[i][j] = x + distort * Math.cos( argx );
                yg1[i][j] = y - distort * Math.cos( argy );

                xg2[i][j] = x + distort * Math.cos( argx ) * Math.cos( argy );
                yg2[i][j] = y - distort * Math.cos( argx ) * Math.cos( argy );
            }
        }

        // Plot using identity transform

        pls.adv( 0 );
        pls.vpor( 0.1, 0.9, 0.1, 0.9 );
        pls.wind( -1.0, 1.0, -1.0, 1.0 );

        pls.psty( 0 );

        pls.shades( z, -1., 1., -1., 1.,
            shedge, fill_width,
            cont_color, cont_width,
            true, xg0, yg0 );

        // Smaller text
        pls.schr( 0.0, 0.75 );
        // Small ticks on the vertical axis
        pls.smaj( 0.0, 0.5 );
        pls.smin( 0.0, 0.5 );

        num_values[0] = NSHADES + 1;
        for ( i = 0; i < NSHADES + 1; i++ )
        {
            values[0][i] = shedge[i];
        }
        pls.colorbar( colorbar_width, colorbar_height,
            PL_COLORBAR_SHADE | PL_COLORBAR_SHADE_LABEL, 0,
            0.005, 0.0, 0.0375, 0.875, 0, 1, 1, 0.0, 0.0,
            cont_color, cont_width,
            label_opts, labels,
            axis_opts,
            axis_ticks, axis_subticks,
            num_values, values );

        // Reset text and tick sizes
        pls.schr( 0.0, 1.0 );
        pls.smaj( 0.0, 1.0 );
        pls.smin( 0.0, 1.0 );

        pls.col0( 1 );
        pls.box( "bcnst", 0.0, 0, "bcnstv", 0.0, 0 );
        pls.col0( 2 );
        pls.lab( "distance", "altitude", "Bogon density" );

        // Plot using 1d coordinate transform

        // Load colour palettes
        pls.spal0( "cmap0_black_on_white.pal" );
        pls.spal1( "cmap1_blue_yellow.pal", true );
        // Reduce colors in cmap 0 so that cmap 1 is useful on a
        //16-color display
        pls.scmap0n( 3 );

        pls.adv( 0 );
        pls.vpor( 0.1, 0.9, 0.1, 0.9 );
        pls.wind( -1.0, 1.0, -1.0, 1.0 );

        pls.psty( 0 );

        pls.shades( z, -1., 1., -1., 1.,
            shedge, fill_width,
            cont_color, cont_width,
            true, xg1, yg1 );

        // Smaller text
        pls.schr( 0.0, 0.75 );
        // Small ticks on the vertical axis
        pls.smaj( 0.0, 0.5 );
        pls.smin( 0.0, 0.5 );

        num_values[0] = NSHADES + 1;
        for ( i = 0; i < NSHADES + 1; i++ )
        {
            values[0][i] = shedge[i];
        }
        pls.colorbar( colorbar_width, colorbar_height,
            PL_COLORBAR_SHADE | PL_COLORBAR_SHADE_LABEL, 0,
            0.005, 0.0, 0.0375, 0.875, 0, 1, 1, 0.0, 0.0,
            cont_color, cont_width,
            label_opts, labels,
            axis_opts,
            axis_ticks, axis_subticks,
            num_values, values );

        // Reset text and tick sizes
        pls.schr( 0.0, 1.0 );
        pls.smaj( 0.0, 1.0 );
        pls.smin( 0.0, 1.0 );

        pls.col0( 1 );
        pls.box( "bcnst", 0.0, 0, "bcnstv", 0.0, 0 );
        pls.col0( 2 );

        pls.lab( "distance", "altitude", "Bogon density" );

        // Plot using 2d coordinate transform

        // Load colour palettes
        pls.spal0( "cmap0_black_on_white.pal" );
        pls.spal1( "cmap1_blue_red.pal", true );
        // Reduce colors in cmap 0 so that cmap 1 is useful on a
        //16-color display
        pls.scmap0n( 3 );

        pls.adv( 0 );
        pls.vpor( 0.1, 0.9, 0.1, 0.9 );
        pls.wind( -1.0, 1.0, -1.0, 1.0 );

        pls.psty( 0 );

        pls.shades( z, -1., 1., -1., 1.,
            shedge, fill_width,
            cont_color, cont_width,
            false, xg2, yg2 );

        // Smaller text
        pls.schr( 0.0, 0.75 );
        // Small ticks on the vertical axis
        pls.smaj( 0.0, 0.5 );
        pls.smin( 0.0, 0.5 );

        num_values[0] = NSHADES + 1;
        for ( i = 0; i < NSHADES + 1; i++ )
        {
            values[0][i] = shedge[i];
        }
        pls.colorbar( colorbar_width, colorbar_height,
            PL_COLORBAR_SHADE | PL_COLORBAR_SHADE_LABEL, 0,
            0.005, 0.0, 0.0375, 0.875, 0, 1, 1, 0.0, 0.0,
            cont_color, cont_width,
            label_opts, labels,
            axis_opts,
            axis_ticks, axis_subticks,
            num_values, values );

        // Reset text and tick sizes
        pls.schr( 0.0, 1.0 );
        pls.smaj( 0.0, 1.0 );
        pls.smin( 0.0, 1.0 );

        pls.col0( 1 );
        pls.box( "bcnst", 0.0, 0, "bcnstv", 0.0, 0 );
        pls.col0( 2 );
        pls.cont( w, 1, XPTS, 1, YPTS, clevel, xg2, yg2 );

        pls.lab( "distance", "altitude", "Bogon density, with streamlines" );

        // Plot using 2d coordinate transform

        // Load colour palettes
        pls.spal0( "" );
        pls.spal1( "", true );
        // Reduce colors in cmap 0 so that cmap 1 is useful on a
        //16-color display
        pls.scmap0n( 3 );

        pls.adv( 0 );
        pls.vpor( 0.1, 0.9, 0.1, 0.9 );
        pls.wind( -1.0, 1.0, -1.0, 1.0 );

        pls.psty( 0 );

        pls.shades( z, -1., 1., -1., 1.,
            shedge, fill_width,
            2, 3.,
            false, xg2, yg2 );

        // Smaller text
        pls.schr( 0.0, 0.75 );
        // Small ticks on the vertical axis
        pls.smaj( 0.0, 0.5 );
        pls.smin( 0.0, 0.5 );

        num_values[0] = NSHADES + 1;
        for ( i = 0; i < NSHADES + 1; i++ )
        {
            values[0][i] = shedge[i];
        }
        pls.colorbar( colorbar_width, colorbar_height,
            PL_COLORBAR_SHADE | PL_COLORBAR_SHADE_LABEL, 0,
            0.005, 0.0, 0.0375, 0.875, 0, 1, 1, 0.0, 0.0,
            2, 3.0,
            label_opts, labels,
            axis_opts,
            axis_ticks, axis_subticks,
            num_values, values );

        // Reset text and tick sizes
        pls.schr( 0.0, 1.0 );
        pls.smaj( 0.0, 1.0 );
        pls.smin( 0.0, 1.0 );

        pls.col0( 1 );
        pls.box( "bcnst", 0.0, 0, "bcnstv", 0.0, 0 );
        pls.col0( 2 );

        pls.lab( "distance", "altitude", "Bogon density" );

        // Note this exclusion API will probably change so don't bother
        // with it for x16.java example.


        //Example with polar coordinates.

        // Load colour palettes
        pls.spal0( "cmap0_black_on_white.pal" );
        pls.spal1( "cmap1_gray.pal", true );
        // Reduce colors in cmap 0 so that cmap 1 is useful on a
        //16-color display
        pls.scmap0n( 3 );

        pls.adv( 0 );
        pls.vpor( .1, .9, .1, .9 );
        pls.wind( -1., 1., -1., 1. );

        pls.psty( 0 );

        // Build new coordinate matrices.

        for ( i = 0; i < XPTS; i++ )
        {
            r = ( (double) i ) / ( XPTS - 1 );
            for ( j = 0; j < YPTS; j++ )
            {
                t         = ( 2. * Math.PI / ( YPTS - 1. ) ) * j;
                xg2[i][j] = r * Math.cos( t );
                yg2[i][j] = r * Math.sin( t );
                z[i][j]   = Math.exp( -r * r ) * Math.cos( 5. * Math.PI * r ) * Math.cos( 5. * t );
            }
        }

        //Need a new shedge to go along with the new data set.

        f2mnmx( z, XPTS, YPTS );
        zmin = fmin;
        zmax = fmax;

        for ( i = 0; i < NSHADES + 1; i++ )
            shedge[i] = zmin + ( zmax - zmin ) * i / NSHADES;

        pls.shades( z, -1., 1., -1., 1.,
            shedge, fill_width,
            cont_color, cont_width,
            false, xg2, yg2 );

        // Smaller text
        pls.schr( 0.0, 0.75 );
        // Small ticks on the vertical axis
        pls.smaj( 0.0, 0.5 );
        pls.smin( 0.0, 0.5 );

        num_values[0] = NSHADES + 1;
        for ( i = 0; i < NSHADES + 1; i++ )
        {
            values[0][i] = shedge[i];
        }
        pls.colorbar( colorbar_width, colorbar_height,
            PL_COLORBAR_SHADE | PL_COLORBAR_SHADE_LABEL, 0,
            0.005, 0.0, 0.0375, 0.875, 0, 1, 1, 0.0, 0.0,
            cont_color, cont_width,
            label_opts, labels,
            axis_opts,
            axis_ticks, axis_subticks,
            num_values, values );

        // Reset text and tick sizes
        pls.schr( 0.0, 1.0 );
        pls.smaj( 0.0, 1.0 );
        pls.smin( 0.0, 1.0 );

// Now we can draw the perimeter.  (If do before, shade stuff may overlap.)
        for ( i = 0; i < PERIMETERPTS; i++ )
        {
            t     = ( 2. * Math.PI / ( PERIMETERPTS - 1 ) ) * i;
            px[i] = Math.cos( t );
            py[i] = Math.sin( t );
        }
        pls.col0( 1 );
        pls.line( px, py );

        // And label the plot.

        pls.col0( 2 );
        pls.lab( "", "", "Tokamak Bogon Instability" );

        // Clean up

        pls.end();
    }
}

//--------------------------------------------------------------------------
//                              End of x16.java
//--------------------------------------------------------------------------