It took me quite a while to get a gnuplot call running from Java instead of the terminal. An example terminal call looks like:
gnuplot -e "filename='histograms/input_10000'; titlename='input_10000'; outputname='histograms/input_10000.pdf'" plot_histograms.gnuplot
The corresponding Java call looks like:
String[] command = {"/usr/bin/gnuplot",
"-e",
"filename='histograms/" + fileNameArr[0] + "'; titlename='" + fileNameArr[0] + "'; outputname='histograms/" + fileNameArr[0] + ".pdf'",
"plot_histograms.gnuplot"};
System.out.println(Arrays.toString(command));
ProcessBuilder pb = new ProcessBuilder(command);
pb.directory(new File(mainPath));
Process process = pb.start();
InputStream is = process.getErrorStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
Note that the quotes around the -e parameters must not be inserted in the command string.
