diff --git a/src/cortecs/tests/test_fit.py b/src/cortecs/tests/test_fit.py
index edd52fd..fe05a8e 100644
--- a/src/cortecs/tests/test_fit.py
+++ b/src/cortecs/tests/test_fit.py
@@ -96,7 +96,7 @@ def test_nan_pca_cube_errors(self):
         i want to make a linalg errror!
         :return:
         """
-        bad_cube = np.zeros((3, 3)) * np.inf
+        bad_cube = np.ones((3, 3)) * np.nan
 
         self.assertRaises(
             ValueError,