diff --git a/poisson/discrete/_discrete_poisson.pyx b/poisson/discrete/_discrete_poisson.pyx
index 75c494bdaf3d6f118727c758ffc13a1f8ebe6732..e1900a9751e37be07d489af4d4f1b56700ced4d7 100644
--- a/poisson/discrete/_discrete_poisson.pyx
+++ b/poisson/discrete/_discrete_poisson.pyx
@@ -6,7 +6,7 @@ import numpy as np
 cimport numpy as np
 
 cpdef find_non_empty(list list_input,
-                     np.ndarray[np.long_t, ndim=1] index_to_test):
+                     np.ndarray[np.int_t, ndim=1] index_to_test):
 
     cdef int position
     cdef long indice