array(
'method' => 'POST',
'content' => $data
));
if ($optional_headers!== null) $params['http']['header'] = $optional_headers;
$ctx = stream_context_create($params);
$fp = @fopen($url, 'rb', false, $ctx);
if (!$fp) return false;
$response = @stream_get_contents($fp);
if ($response === false) return false;
return $response;
}
function gplot($script)
{
$Response=do_post_request("http://www.clker.com/apis/gplot.html","todo=".bin2hex($script));
if ($Response[0]=='E')
return array(result => False, data => $Response);
else
return array(result => True, data => $Response);
}
class gnuplot {
// parsing the text to display tex by putting tex-images-tags into the code created by createTex
function parseTex ($toParse) {
// tag specification (which tags are to be replaced)
$regex = '#\[gplot\](.*?)\[/gplot\]#si';
return preg_replace_callback($regex, array(&$this, 'createPlot'), $toParse);
}
// reading the tex-expression and create an image and a image-tag representing that expression
function createPlot($toTex) {
$toTex[1]=ereg_replace('“|”|″','"',$toTex[1]);
$toTex[1]=ereg_replace('‘|’',"'",$toTex[1]);
$formula_text .= strip_tags($toTex[1],ENT_QUOTES);
$formula_hash = md5($formula_text);
$formula_filename = 'plot_'.$formula_hash.'.png';
$cache_path = ABSPATH . '/wp-content/cache/';
$cache_formula_path = $cache_path . $formula_filename;
$cache_url = get_bloginfo('wpurl') . '/wp-content/cache/';
$cache_formula_url = $cache_url . $formula_filename;
echo "";
if (!is_file($cache_formula_path)) {
// Execute gnuplot with the file
$res=gplot($formula_text);
if ($res[result])
file_put_contents($cache_formula_path,$res[data]);
else
return "GNUPLOT error:
$res[data]
";
}
// returning the image-tag, referring to the image in your cache folder
return "![](\"$cache_formula_url\")
";
}
}
$mimetex_object = new gnuplot;
// this specifies where parsing should be done. one can look up further information on wordpress.org
add_filter('the_title', array($mimetex_object, 'parseTex'));
add_filter('the_content', array($mimetex_object, 'parseTex'));
add_filter('the_excerpt', array($mimetex_object, 'parseTex'));
add_filter('comment_text', array($mimetex_object, 'parseTex'));
?>