Hello, I am writing a C program, which uses a class I have written in Python. The class has a method 'operate_image' that receives as parameters a Numeric array, an integer and a float. The class has been repeatedly used with no problems. When I try to call the method I use: pres_fi=PyObject_CallMethod(pFI,"operate_image","(Oif)",parray,1,1.0); But the result (pres-fi) is NULL. I have tested pFI to exist and to have the mentioned method, with no troubles. So it seems to me that PyObject_CallMethod is casting down the parray object, which is a PyArrayObject. That is the reason of malfunctioning. Questions: 1) Is my interpratation right? 2) Which would be the correct way to do such an operation? It is the first time I write an Python embedded/extension, so I am quite lost. Thanks in advance, Aureli ################################# Aureli Soria Frisch Fraunhofer IPK Dept. Pattern Recognition post: Pascalstr. 8-9, 10587 Berlin, Germany e-mail:aureli@ipk.fhg.de fon: +49 30 39006-150 fax: +49 30 3917517 #################################