diff --git a/minisom.py b/minisom.py
index 2380e0e..780f853 100644
--- a/minisom.py
+++ b/minisom.py
@@ -864,10 +864,10 @@ def test_random_weights_init(self):
     def test_pca_weights_init(self):
         som = MiniSom(2, 2, 2)
         som.pca_weights_init(array([[1.,  0.], [0., 1.], [1., 0.], [0., 1.]]))
-        expected = array([[[-1.41421356,  0.],
-                           [0.,  1.41421356]],
-                          [[0., -1.41421356],
-                           [1.41421356,  0.]]])
+        expected = array([[[1.57735027, -0.42264973],
+                           [0.42264973, -1.57735027]],
+                          [[-0.42264973, 1.57735027],
+                           [-1.57735027, 0.42264973]]])
         assert_array_almost_equal(som._weights, expected)
 
     def test_distance_map(self):