/usr/share/octave/packages/interval-2.1.0/@infsup/private/str2decimal.m is in octave-interval 2.1.0-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 | ## Copyright 2014-2016 Oliver Heimlich
##
## This program is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 3 of the License, or
## (at your option) any later version.
##
## This program 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 General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program; if not, see <http://www.gnu.org/licenses/>.
## -*- texinfo -*-
## @documentencoding UTF-8
## @deffun str2decimal (@var{S})
##
## Parse a decimal number string @var{S} and split the sign, the mantissa and
## the exponent information.
##
## The input number format is [+-]d[,.]d[[eE][+-]d] (cf. str2double).
##
## Limitations: The decimal exponent of the input format must be a number
## between -2^53 (exclusive) and +2^53 (exclusive).
## The number itself either must equal zero or its absolute value must be
## between 10^(-2^62) (inclusive) and 10^(2^63 - 1) (exclusive).
##
## Sign: true (-) or false (+)
##
## Mantissa: Vector that holds the decimal digits after the decimal point. The
## first digit is not zero. Trailing zeroes are removed.
##
## Exponent: Integral exponent (base 10).
##
## @example
## @group
## x = str2decimal ("-12.3e14")
## @result{}
## x.s = 1
## x.m = [1 2 3]'
## x.e = 16
## y = str2decimal ("0.00123e-14")
## @result{}
## y.s = 0
## y.m = [1 2 3]'
## y.e = -12
## z = str2decimal ("0")
## @result{}
## z.s = 0
## z.m = []
## z.e = 0
## @end group
## @end example
## @seealso{double2decimal}
## @end deffun
## Author: Oliver Heimlich
## Created: 2014-09-27
function decimal = str2decimal (string)
## Strip Sign
if (isempty (string))
decimal.s = false;
else
decimal.s = (string(1) == "-");
if (strfind("+-", string(1)))
string = string (2:end);
endif
endif
## Split mantissa & exponent
[decimal.m, decimal.e] = strtok (string, "eE");
## Convert exponent from string to number
if (isempty (decimal.e))
decimal.e = int64(0); # 10 ^ 0 = 1
else
if (strfind (decimal.e, ".") || strfind (decimal.e, ","))
error ("interval:InvalidOperand", ...
["invalid decimal number with rational exponent: " string]);
endif
decimal.e = str2double (decimal.e(2:end)); # remove “e” and convert
if (isnan (decimal.e) || ... # greater than realmax or illegal format
abs(decimal.e) >= pow2 (53)) # possibly lost precision
error ("interval:InvalidOperand", ...
["invalid decimal number with big/invalid exponent: " string]);
endif
decimal.e = int64 (decimal.e);
endif
## Normalize mantissa: remove leading zeroes within string representation
## before decimal point. This does not affect the exponent and is therefore
## preferred over the normalization below, which might produce overflow errors.
decimal.m = decimal.m(find(decimal.m ~= "0", 1):end);
## Split Mantissa at decimal point
decimal.m = strsplit (decimal.m, {".",","});
switch length(decimal.m)
case 0
decimal.m = {"", ""};
case 1
decimal.m{2} = "";
case 2
# nothing to do
otherwise
error ("interval:InvalidOperand", ...
["invalid decimal number with multiple decimal points: " ...
string]);
endswitch
## Normalize mantissa string: move decimal point to the left
if (decimal.e + length (decimal.m{1}) >= intmax (class (decimal.e)))
error ("interval:InvalidOperand", ...
["exponent overflow during normalization: " string ]);
endif
decimal.e += length (decimal.m{1});
decimal.m = strcat (decimal.m{1}, decimal.m{2});
## Convert mantissa to numeric vector with decimal digits
decimal.m = str2num (decimal.m');
## Normalize mantissa: remove leading zeroes
firstnonzerodigit = find (decimal.m ~= 0, 1, "first");
if (firstnonzerodigit > 1)
decimal.m = decimal.m(firstnonzerodigit:end);
if (decimal.e - (firstnonzerodigit - 1) <= intmin (class (decimal.e)))
error ("interval:InvalidOperand", ...
["exponent overflow during normalization: " string ]);
endif
decimal.e -= firstnonzerodigit - 1;
elseif (isempty (firstnonzerodigit)) # all digits are zero
decimal.s = false;
decimal.m = [];
decimal.e = int64 (0);
return
endif
## Normalize mantissa: remove trailing zeroes;
lastnonzerodigit = find (decimal.m ~= 0, 1, "last");
if (lastnonzerodigit < length (decimal.m))
decimal.m = decimal.m(1:lastnonzerodigit);
endif
endfunction
|