//-------------------------------------------------------------------------- // Copyright (C) 2001 Geoffrey Furnish // Copyright (C) 2001, 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 4 in Java. //-------------------------------------------------------------------------- package plplot.examples; import plplot.core.*; import static plplot.core.plplotjavacConstants.*; import java.lang.Math; class x04 { PLStream pls = new PLStream(); public static void main( String[] args ) { new x04( args ); } public x04( String[] args ) { // Parse and process command line arguments. pls.parseopts( args, PL_PARSE_FULL | PL_PARSE_NOPROGRAM ); // Initialize plplot. pls.init(); pls.font( 2 ); // Make log plots using two different styles. plot1( 0 ); plot1( 1 ); pls.end(); } // Log-linear plot. void plot1( int type ) { int i; double[] freql = new double[101]; double[] ampl = new double[101]; double[] phase = new double[101]; double f0, freq; int nlegend; String[] text; String[] symbols; int[] opt_array; int[] text_colors; int[] line_colors; int[] line_styles; double[] line_widths; int[] symbol_numbers; int[] symbol_colors; double[] symbol_scales; double[] legend_width = new double[1]; double[] legend_height = new double[1]; 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 = Math.pow( 10.0, freql[i] ); // Unbelievably, Java has no log10() that I can find... ampl[i] = 20.0 * Math.log( 1.0 / Math.sqrt( 1.0 + Math.pow( ( freq / f0 ), 2. ) ) ) / Math.log( 10. ); phase[i] = -( 180.0 / Math.PI ) * Math.atan( 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( freql, ampl ); pls.col0( 2 ); pls.ptex( 1.6, -30.0, 1.0, -20.0, 0.5, "-20 dB/decade" ); // Put labels on. pls.col0( 1 ); pls.mtex( "b", 3.2, 0.5, 0.5, "Frequency" ); pls.mtex( "t", 2.0, 0.5, 0.5, "Single Pole Low-Pass Filter" ); pls.col0( 2 ); pls.mtex( "l", 5.0, 0.5, 0.5, "Amplitude (dB)" ); nlegend = 1; // 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( freql, phase ); pls.string( freql, phase, "#(728)" ); pls.col0( 3 ); pls.mtex( "r", 5.0, 0.5, 0.5, "Phase shift (degrees)" ); nlegend = 2; } text = new String[nlegend]; symbols = new String[nlegend]; opt_array = new int[nlegend]; text_colors = new int[nlegend]; line_colors = new int[nlegend]; line_styles = new int[nlegend]; line_widths = new double[nlegend]; symbol_numbers = new int[nlegend]; symbol_colors = new int[nlegend]; symbol_scales = new double[nlegend]; // Draw a legend // First legend entry. opt_array[0] = PL_LEGEND_LINE; text_colors[0] = 2; text[0] = "Amplitude"; line_colors[0] = 2; line_styles[0] = 1; line_widths[0] = 1.; // note from the above opt_array the first symbol (and box) indices // do not have to be specified EXCEPT for symbols. // Although this is unused, it can't be undefined as the String // array is copied as part of the java bindings. symbols[0] = " "; // Second legend entry. if ( nlegend == 2 ) { opt_array[1] = PL_LEGEND_LINE | PL_LEGEND_SYMBOL; text_colors[1] = 3; text[1] = "Phase shift"; line_colors[1] = 3; line_styles[1] = 1; line_widths[1] = 1.; symbol_colors[1] = 3; symbol_scales[1] = 1.; symbol_numbers[1] = 4; symbols[1] = "#(728)"; } // 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, 0.1, 15, 1, 1, 0, 0, opt_array, 1.0, 1.0, 2.0, 1., text_colors, text, null, null, null, null, line_colors, line_styles, line_widths, symbol_colors, symbol_scales, symbol_numbers, symbols ); } } //-------------------------------------------------------------------------- // End of x04.java //--------------------------------------------------------------------------