0

I wrote a simple script. It integrates a DE:

from scipy import integrate

def rhs(t, x):
    return x

solver = integrate.ode(rhs)
solver.set_integrator('dopri5')
solver.set_initial_value(1.0, 0.0)
solver.integrate(0.2)
print solver.y

It works correct. But if I cythonize it and load from another python script, I get the error:

capi_return is NULL
Call-back cb_fcn_in___user__routines failed.
Traceback (most recent call last):
  File "...\tmp\build\lib.win-amd64-2.7\test2.py", line 1, in <module>
    import test
  File "test.py", line 9, in init test (test.c:1113)
  File "...\Anaconda\lib\site-packages\scipy\integrate\_ode.py", line 408, in integrate
    self.f_params, self.jac_params)
  File "...\Anaconda\lib\site-packages\scipy\integrate\_ode.py", line 1032, in run
    tuple(self.call_args) + (f_params,)))
  File "test.py", line 3, in test.rhs (test.c:748)
TypeError: rhs() takes exactly 2 positional arguments (1 given)

The setup.py script contains:

from distutils.core import setup
from Cython.Build import cythonize

ext_modules = cythonize(['*.py'], exclude=['setup.py'])
setup(name='some_module', version='1.0', description='bla bla', ext_modules=ext_modules)

In the second script I just call

import test

P.S. I use anaconda python-2.7 for windows7, x64. I've got the latest version of scipy. I created the testproject gitlab.

Maksim Surov
  • 603
  • 6
  • 22
  • 1
    `cythonize` may be able to speed up your `rhs` function. It can't touch the rest of the code which uses the imported `integrate` and its `solver` object. I'd suggest putting `rhs` in separate file, and `cythonize` only that. – hpaulj Aug 12 '16 at 17:42
  • 1
    This is the same bug as http://stackoverflow.com/questions/38263794/using-scipy-integrate-ode-with-cython. Your best bet is probably to report is to the developers https://github.com/cython/cython/issues – DavidW Aug 13 '16 at 09:15

0 Answers0