inconvenientes para crear imagen con jpgraph y postgresql

[Montes28]

Hola amigos espero me puedan ayudar, me encuentro generando una grafica con jpgraph y postgresql pero me sale el siguiente error


Chosen locale file ("lang/en.inc.php") for error messages does not exist or is not readable for the PHP process. Please make sure that the file exists and that the file permissions are such that the PHP process is allowed to read this file.


este es mi codigo

Código PHP:

<?php // content="text/plain; charset=utf-8"
require_once('jpgraph/jpgraph.php');
require_once('jpgraph/jpgraph_bar.php');
 
//$datay1=array(13,8,19,7,17,6);
//$datay2=array(4,5,2,7,5,25);
 
 
        $servidor = 'localhost';
        $bd = 'indumontes';
        $usuario = 'postgres';
        $contrasenia = 'hoe798cs';
        $tabla = 'factura';
        
 
        global $servidor, $bd, $usuario, $contrasenia;
        $db = new PDO('pgsql:host=' . $servidor . ';dbname=' . $bd, $usuario, $contrasenia);
 
        $consulta = $db->prepare("SELECT vendedor,total FROM $tabla");
        $consulta->execute();
 
        while($fila = $consulta->fetch(PDO::FETCH_ASSOC))
        {
        $datay1[] = $fila[0];
        $datay2[] = $fila[1];
        }
 
 
 
 
// Create the graph.
$graph = new Graph(550,300);
$graph->SetScale('textlin');
$graph->SetMarginColor('white');
 
// Setup title
$graph->title->Set('Acc bar with gradient');
 
// Create the first bar
$bplot = new BarPlot($datay1);
$bplot->SetFillGradient('AntiqueWhite2','AntiqueWhite4:0.8',GRAD_VERT);
$bplot->SetColor('darkred');
 
// Create the second bar
$bplot2 = new BarPlot($datay2);
$bplot2->SetFillGradient('olivedrab1','olivedrab4',GRAD_VERT);
$bplot2->SetColor('darkgreen');
 
// And join them in an accumulated bar
$accbplot = new AccBarPlot(array($bplot,$bplot2));
$graph->Add($accbplot);
 
$graph->Stroke();
 
 
 
?>
 

que estoy haciendo mal?