Function ufunc_outer

numpy/core/src/umath/ufunc_object.c:5765–5789

* op.outer(a,b) is equivalent to op(a[:,NewAxis,NewAxis,etc.],b) * where a has b.ndim NewAxis terms appended. * * The result has dimensions a.ndim + b.ndim */

 * The result has dimensions a.ndim + b.ndim
 */
static PyObject *
ufunc_outer(PyUFuncObject *ufunc,
        PyObject *const *args, Py_ssize_t len_args, PyObject *kwnames)
{
    if (ufunc->core_enabled) {
        PyErr_Format(PyExc_TypeError,
                     "method outer is not allowed in ufunc with non-trivial"\
                     " signature");
        return NULL;
    }

    if (ufunc->nin != 2) {
        PyErr_SetString(PyExc_ValueError,
                        "outer product only supported "\
                        "for binary functions");
        return NULL;
    }

    if (len_args != 2) {
        PyErr_SetString(PyExc_TypeError, "exactly two arguments expected");
        return NULL;
    }

    return ufunc_generic_fastcall(ufunc, args, len_args, kwnames, NPY_TRUE);
}


static PyObject *