Programmatic access to GNU Octave

octave_interface.php

<?php

$octave_command = "octave --no-window-system -q";

$spec = array(
   0 => array("pipe", "r"),
   1 => array("pipe", "w"),
   2 => array("file", "/tmp/octave_stderr.txt", "a")
);

$proc = proc_open($octave_command, $spec, $pipes, '/tmp');

if (is_resource($proc)) {

    while($command = fgets(STDIN)) {
        echo 'REQUEST : '.$command;
        fwrite($pipes[0], $command);
        $line = fgets($pipes[1]);
        list(,$ans) = explode('ans =',$line,2);
        if(in_array(trim($command),array('quit','exit'))) {
            break;
        }
        echo 'RESPONSE: '.ltrim($ans);
    }

    fclose($pipes[0]);
    fclose($pipes[1]);

    $return = proc_close($proc);

    echo 'EXITING: '.$return.PHP_EOL;
}