/*
* Gnuplot Call
*
* Copyright © 2009 Tony Saad <remineur@gmail.com>
* (Written by Tony Saad <remineur@gmail.com>)
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
void plotResults(double* xData, double* yData, int dataSize);
int main() {
  int i = 0;
  int nIntervals = 100;
  double intervalSize = 1.0;
  double stepSize = intervalSize/nIntervals;
  double* xData = (double*) malloc((nIntervals+1)*sizeof(double));
  double* yData = (double*) malloc((nIntervals+1)*sizeof(double));
  xData[0] = 0.0;
  double x0 = 0.0;
  for (i = 0; i < nIntervals; i++) {
      x0 = xData[i];
      xData[i+1] = x0 + stepSize;
  }
  for (i = 0; i <= nIntervals; i++) {
      x0 = xData[i];
      yData[i] = sin(x0)*cos(10*x0);
  }
  plotResults(xData,yData,nIntervals);
  return 0;
}
void plotResults(double* xData, double* yData, int dataSize) {
  FILE *gnuplotPipe,*tempDataFile;
  char *tempDataFileName;
  double x,y;
  int i;
  tempDataFileName = "tempData";
  gnuplotPipe = popen("c:\\gnuplot\\bin\\pgnuplot -persist","w");
  if (gnuplotPipe) {
      fprintf(gnuplotPipe,"plot \"%s\" with lines\n",tempDataFileName);
      fflush(gnuplotPipe);
      tempDataFile = fopen(tempDataFileName,"w");
      for (i=0; i <= dataSize; i++) {
          x = xData[i];
          y = yData[i];
          fprintf(tempDataFile,"%lf %lf\n",x,y);
      }
      fclose(tempDataFile);
      printf("press enter to continue...");
      getchar();
      remove(tempDataFileName);
      fprintf(gnuplotPipe,"exit \n");
  } else {
      printf("gnuplot not found...");
  }
}