Cython import function from other pyx

Question

Two pyx files,

f1.pyx

cpdef double func1():
     return 0.01

f2.pyx

from f1 cimport func1

How could I import func1 from f1.pyx? The reason is that I have different sections and want to put them in separate pyx files. But I couldn't import after I break them up.

Answer 1

When you cimport a function from another file Cython needs a definition file (a *.pxd file) as well as the implementation file. (see here for the relevant section of the documentation)

If you also create a file called f1.pxd containing the following:

cpdef double func1()

Your example should compile.