diff --git a/python/_cosmomath.pyx b/python/_cosmomath.pyx
index 0aa5fd4..e5ab880 100644
--- a/python/_cosmomath.pyx
+++ b/python/_cosmomath.pyx
@@ -14,7 +14,7 @@ cdef extern from "numpy/npy_common.h":
 cdef extern from "special_math.hpp" namespace "CosmoTool":
    T log_modified_bessel_first_kind[T](T v, T z) nogil except +
 
-cdef extern from "numpy_adaptor.hpp" namespace "CosmoTool":
+cdef extern from "numpy_adaptors.hpp" namespace "CosmoTool":
    void parallel_ufunc_dd_d[T,IT](char **args, IT* dimensions, IT* steps, void *func)
 
 
diff --git a/src/numpy_adaptors.hpp b/src/numpy_adaptors.hpp
index fe3962c..196206b 100644
--- a/src/numpy_adaptors.hpp
+++ b/src/numpy_adaptors.hpp
@@ -8,7 +8,7 @@ namespace CosmoTool {
     IT i;
     IT n = dimensions[0];
     char *in = args[0], *in2 = args[1], *out = args[2];
-    IT in_step = steps[0], in2_step = args[1], out_step = steps[2];
+    IT in_step = steps[0], in2_step = steps[1], out_step = steps[2];
 
     double tmp;
     typedef double (*F_t)(double,double);