Fatal error: Uncaught Error: Undefined constant "STDERR" in /var/www/html/tennisdata/PHPlot/test/run_test.php:62 Stack trace: #0 /var/www/html/tennisdata/PHPlot/test/run_test.php(534): usage() #1 {main} thrown in /var/www/html/tennisdata/PHPlot/test/run_test.php on line 62