Hello, I'm trying to figure out what is the proper type for indexing arrays. Is it safe to use Py_ssize_t although PyArrayObject dimensions are of Py_intptr_t (intp) type or use intp instead of Py_ssize_t? Is there any platform on which these two types has different size or range? References: [1] http://www.python.org/dev/peps/pep-0353/#why-not-py-intptr-t [2] numpy 0.9.6, arrayobject.c: static _int_or_ssize_t array_length(PyArrayObject *self) { if (self->nd != 0) { return self->dimensions[0]; } else { PyErr_SetString(PyExc_TypeError, "len() of unsized object"); return -1; } } // self->dimensions is of intp* type [3] http://svn.python.org/projects/python/branches/ssize_t/Include/abstract.h PyAPI_FUNC(int) PyObject_AsReadBuffer(PyObject *obj, const void **buffer, Py_ssize_t *buffer_len); -- best, fw