/usr/share/doc/libplplot12/examples/c++/x26.cc is in libplplot-dev 5.10.0+dfsg2-0.1ubuntu2.
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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 | // -*- coding: utf-8; -*-
//
//--------------------------------------------------------------------------
// $Id: x26.cc 12336 2013-05-10 19:01:13Z andrewross $
// Multi-lingual version of the first page of example 4.
//--------------------------------------------------------------------------
//
//--------------------------------------------------------------------------
// Copyright (C) 2006 Alan W. Irwin
// Copyright (C) 2006 Andrew Ross
//
// Thanks to the following for providing translated strings for this example:
// Valery Pipin (Russian)
//
// 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
//--------------------------------------------------------------------------
// This example designed just for devices (e.g., psttfc and the
// cairo-related devices) that use the pango and fontconfig libraries. The
// best choice of glyph is selected by fontconfig and automatically rendered
// by pango in way that is sensitive to complex text layout (CTL) language
// issues for each unicode character in this example. Of course, you must
// have the appropriate TrueType fonts installed to have access to all the
// required glyphs.
//
// Translation instructions: The strings to be translated are given by
// x_label, y_label, alty_label, title_label, and line_label below. The
// encoding used must be UTF-8.
//
// The following strings to be translated involve some scientific/mathematical
// jargon which is now discussed further to help translators.
//
// (1) dB is a decibel unit, see http://en.wikipedia.org/wiki/Decibel .
// (2) degrees is an angular measure, see
// http://en.wikipedia.org/wiki/Degree_(angle) .
// (3) low-pass filter is one that transmits (passes) low frequencies.
// (4) pole is in the mathematical sense, see
// http://en.wikipedia.org/wiki/Pole_(complex_analysis) . "Single Pole"
// means a particular mathematical transformation of the filter function has
// a single pole, see
// http://ccrma.stanford.edu/~jos/filters/Pole_Zero_Analysis_I.html .
// Furthermore, a single-pole filter must have an inverse square decline
// (or -20 db/decade). Since the filter plotted here does have that
// characteristic, it must by definition be a single-pole filter, see also
// http://www-k.ext.ti.com/SRVS/Data/ti/KnowledgeBases/analog/document/faqs/1p.htm
// (5) decade represents a factor of 10, see
// http://en.wikipedia.org/wiki/Decade_(log_scale) .
//--------------------------------------------------------------------------
// Implementation of PLplot example 26 in C++.
//--------------------------------------------------------------------------
#include "plc++demos.h"
#ifdef PL_USE_NAMESPACE
using namespace std;
#endif
static const char *x_label[] = {
"Frequency",
"Частота",
NULL
};
static const char *y_label[] = {
"Amplitude (dB)",
"Амплитуда (dB)",
NULL
};
static const char *alty_label[] = {
"Phase shift (degrees)",
"Фазовый сдвиг (градусы)",
NULL
};
// Short rearranged versions of y_label and alty_label.
static const char *legend_text[][2] = {
{ "Amplitude", "Phase shift" },
{ "Амплитуда", "Фазовый сдвиг" }
};
static const char *title_label[] = {
"Single Pole Low-Pass Filter",
"Однополюсный Низко-Частотный Фильтр",
NULL
};
static const char *line_label[] = {
"-20 dB/decade",
"-20 dB/десяток",
NULL
};
class x26 {
public:
x26( int, const char ** );
void plot1( int, const char*, const char*, const char*, const char**, const char*, const char* );
private:
// Class data
plstream *pls;
};
x26::x26( int argc, const char ** argv )
{
int i;
// plplot initialization
pls = new plstream();
// Parse and process command line arguments.
pls->parseopts( &argc, argv, PL_PARSE_FULL );
// Initialize PLplot.
pls->init();
pls->font( 2 );
// Make log plots using two different styles.
i = 0;
while ( x_label[i] != NULL )
{
plot1( 0, x_label[i], y_label[i], alty_label[i], legend_text[i],
title_label[i], line_label[i] );
i++;
}
// pls->end();
delete pls;
}
// Log-linear plot.
void x26::plot1( int type, const char *x_label, const char *y_label,
const char *alty_label, const char **legend_text,
const char *title_label, const char *line_label )
{
int i;
PLFLT *freql = new PLFLT[101];
PLFLT *ampl = new PLFLT[101];
PLFLT *phase = new PLFLT[101];
PLFLT f0, freq;
PLINT nlegend = 2;
PLINT opt_array[2];
PLINT text_colors[2];
PLINT line_colors[2];
PLINT line_styles[2];
PLFLT line_widths[2];
PLINT symbol_numbers[2], symbol_colors[2];
PLFLT symbol_scales[2];
const char *symbols[2];
PLFLT legend_width, legend_height;
pls->adv( 0 );
// Set up data for log plot.
f0 = 1.0;
for ( i = 0; i <= 100; i++ )
{
freql[i] = -2.0 + i / 20.0;
freq = pow( 10.0, (double) freql[i] );
ampl[i] = 20.0 * log10( 1.0 / sqrt( 1.0 + pow( (double) ( freq / f0 ), 2. ) ) );
phase[i] = -( 180.0 / M_PI ) * atan( (double) ( freq / f0 ) );
}
pls->vpor( 0.15, 0.85, 0.1, 0.9 );
pls->wind( -2.0, 3.0, -80.0, 0.0 );
// Try different axis and labelling styles.
pls->col0( 1 );
switch ( type )
{
case 0:
pls->box( "bclnst", 0.0, 0, "bnstv", 0.0, 0 );
break;
case 1:
pls->box( "bcfghlnst", 0.0, 0, "bcghnstv", 0.0, 0 );
break;
}
// Plot ampl vs freq.
pls->col0( 2 );
pls->line( 101, freql, ampl );
pls->col0( 2 );
pls->ptex( 1.6, -30.0, 1.0, -20.0, 0.5, line_label );
// Put labels on.
pls->col0( 1 );
pls->mtex( "b", 3.2, 0.5, 0.5, x_label );
pls->mtex( "t", 2.0, 0.5, 0.5, title_label );
pls->col0( 2 );
pls->mtex( "l", 5.0, 0.5, 0.5, y_label );
// For the gridless case, put phase vs freq on same plot.
if ( type == 0 )
{
pls->col0( 1 );
pls->wind( -2.0, 3.0, -100.0, 0.0 );
pls->box( "", 0.0, 0, "cmstv", 30.0, 3 );
pls->col0( 3 );
pls->line( 101, freql, phase );
pls->string( 101, freql, phase, "*" );
pls->col0( 3 );
pls->mtex( "r", 5.0, 0.5, 0.5, alty_label );
}
// Draw a legend
// First legend entry.
opt_array[0] = PL_LEGEND_LINE;
text_colors[0] = 2;
line_colors[0] = 2;
line_styles[0] = 1;
line_widths[0] = 1.0;
// note from the above opt_array the first symbol (and box) indices
// do not have to be specified
// Second legend entry.
opt_array[1] = PL_LEGEND_LINE | PL_LEGEND_SYMBOL;
text_colors[1] = 3;
line_colors[1] = 3;
line_styles[1] = 1;
line_widths[1] = 1.0;
symbol_colors[1] = 3;
symbol_scales[1] = 1.;
symbol_numbers[1] = 4;
symbols[1] = "*";
// from the above opt_arrays we can completely ignore everything
// to do with boxes.
pls->scol0a( 15, 32, 32, 32, 0.70 );
pls->legend( &legend_width, &legend_height,
PL_LEGEND_BACKGROUND | PL_LEGEND_BOUNDING_BOX, 0,
0.0, 0.0, 0.10, 15,
1, 1, 0, 0,
nlegend, opt_array,
1.0, 1.0, 2.0,
1., text_colors, (const char * const *) legend_text,
NULL, NULL, NULL, NULL,
line_colors, line_styles, line_widths,
symbol_colors, symbol_scales, symbol_numbers,
(const char **) symbols );
delete[] freql;
delete[] ampl;
delete[] phase;
}
int main( int argc, const char ** argv )
{
x26 *x = new x26( argc, argv );
delete x;
}
//--------------------------------------------------------------------------
// End of x26.cc
//--------------------------------------------------------------------------
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