Cython: How to declare default values in pxd files

Question

I have a function I'd like to abstract into an importable module:

cdef list generate_random_vectors(int num_vectors, int length, float scale=1):
    cdef list return_list
    np.random.seed()
    return_list = []
    for n in range(num_vectors):
    return_list.append((1 - 2 * np.random.rand(length)) / scale)
    return return_list

To put this in a module, I have to define it in the pxd file.

When I try this:

cdef list generate_random_vectors(int num_vectors, int length, float scale)

I get the error: Function signature does not match previous declaration.

When I try this:

cdef list generate_random_vectors(int num_vectors, int length, float scale=1)

I get the error: Expected ')', found 'INT'

Answer 1

Found it. The syntax is different in pxd files.

I need to use:

cdef list generate_random_vectors(int num_vectors, int length, float scale=*)