/usr/share/doc/libplplot11/examples/octave/x04c.m is in octave-plplot 5.9.9-2ubuntu2.
This file is owned by root:root, with mode 0o644.
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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 | ## Copyright (C) 1998, 1999, 2000 Joao Cardoso.
##
## 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 2 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.
##
## This file is part of plplot_octave.
## It is based on the corresponding demo function of PLplot.
## Illustration of logarithmic axes, and redefinition of window.
## this file defines several functions:
1;
function ix04c
## Parse and process command line arguments */
## (void) plparseopts(&argc, argv, PL_PARSE_FULL);
## Initialize plplot */
plinit();
plfont(2);
## Make log plots using two different styles. */
plot1(0);
plot1(1);
plend1();
endfunction
## Log-linear plot.
function plot1(type)
global PL_LEGEND_LINE PL_LEGEND_SYMBOL PL_LEGEND_BACKGROUND PL_LEGEND_BOUNDING_BOX
pladv(0);
## Set up data for log plot */
f0 = 1.0;
i=0:100;
freql = -2.0 + i / 20.0;
freq = 10.0 .^ freql;
ampl = 20.0 * log10(1.0 ./ sqrt(1.0 + (freq ./ f0).^ 2.));
phase = -(180.0 / 3.141592654) * atan(freq ./ f0);
plvpor(0.15, 0.85, 0.1, 0.9);
plwind(-2.0, 3.0, -80.0, 0.0);
## Try different axis and labelling styles. */
plcol0(1);
switch (type)
case 0
plbox("bclnst", 0.0, 0, "bnstv", 0.0, 0);
case 1
plbox("bcfghlnst", 0.0, 0, "bcghnstv", 0.0, 0);
endswitch
## Plot ampl vs freq */
plcol0(2);
plline(freql', ampl');
plcol0(2);
plptex(1.6, -30.0, 1.0, -20.0, 0.5, "-20 dB/decade");
## Put labels on */
plcol0(1);
plmtex("b", 3.2, 0.5, 0.5, "Frequency");
plmtex("t", 2.0, 0.5, 0.5, "Single Pole Low-Pass Filter");
plcol0(2);
plmtex("l", 5.0, 0.5, 0.5, "Amplitude (dB)");
## For the gridless case, put phase vs freq on same plot */
if (type == 0)
plcol0(1);
plwind(-2.0, 3.0, -100.0, 0.0);
plbox("", 0.0, 0, "cmstv", 30.0, 3);
plcol0(3);
plline(freql', phase');
plstring(freql', phase', "*");
plcol0(3);
plmtex("r", 5.0, 0.5, 0.5, "Phase shift (degrees)");
nlegend = 2;
else
nlegend = 1;
endif
## Draw a legend.
## Set up legend arrays with the correct size, type. In octave this may
## be done by clearing the array (in case it was used before) and then
## writing the last element of the array with a placeholder of the right
## type. Note that for strings the right placeholder length doesn't
## matter. Octave keeps track of the longest string in each array and pads
## out all other members with blanks to that length if a subsequent string
## assignment for an array element exceeds that length.
opt_array = 0;
text_colors = 0;
text = " ";
line_colors = 0;
line_styles = 0;
line_widths = 0;
symbol_colors = 0;
symbol_scales = 0.;
symbol_numbers = 0;
symbols = " ";
opt_array(nlegend,1) = 0;
text_colors(nlegend,1) = 0;
text(nlegend,1:length(" ")) = " ";
line_colors(nlegend,1) = 0;
line_styles(nlegend,1) = 0;
line_widths(nlegend,1) = 0;
symbol_colors(nlegend,1) = 0;
symbol_scales(nlegend,1) = 0.;
symbol_numbers(nlegend,1) = 0;
symbols(nlegend,1:length(" ")) = " ";
## Only specify legend data that are required according to the
## value of opt_array for that entry.
## Data for first legend entry.
opt_array(1) = PL_LEGEND_LINE;
text_colors(1) = 2;
text(1,1:length("Amplitude")) = "Amplitude";
line_colors(1) = 2;
line_styles(1) = 1;
line_widths(1) = 1;
## Data for second legend entry.
if(nlegend > 1)
opt_array(2) = bitor(PL_LEGEND_LINE, PL_LEGEND_SYMBOL);
text_colors(2) = 3;
text(2,1:length("Phase shift")) = "Phase shift";
line_colors(2) = 3;
line_styles(2) = 1;
line_widths(2) = 1;
symbol_colors(2) = 3;
symbol_scales(2) = 1.;
symbol_numbers(2) = 4;
symbols(2,1:length("*")) = "*";
endif
plscol0a( 15, 32, 32, 32, 0.70 );
[legend_width, legend_height] = \
pllegend( bitor(PL_LEGEND_BACKGROUND, PL_LEGEND_BOUNDING_BOX), 0, 0.0, 0.0,
0.1, 15, 1, 1, 0, 0, opt_array, 1.0, 1.0, 2.0,
1., text_colors, text,
[], [], [], [],
line_colors, line_styles, line_widths,
symbol_colors, symbol_scales, symbol_numbers, symbols );
endfunction
ix04c
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