diff --git a/skimage/transform/tests/test_hough_transform.py b/skimage/transform/tests/test_hough_transform.py
index 3eaf92bf..0e6c6573 100644
--- a/skimage/transform/tests/test_hough_transform.py
+++ b/skimage/transform/tests/test_hough_transform.py
@@ -140,9 +140,11 @@ def test_hough_circle():
     y, x = circle_perimeter(y_0, x_0, radius)
     img[x, y] = 1
 
-    out = tf.hough_circle(img, radius)
-    out = tf.hough_circle(img, [radius])
+    out1 = tf.hough_circle(img, radius)
+    out2 = tf.hough_circle(img, [radius])
+    assert_equal(out1,out2)
     out = tf.hough_circle(img, np.array([radius], dtype=np.intp))
+    assert_equal(out,out1)
     x, y = np.where(out[0] == out[0].max())
     assert_equal(x[0], x_0)
     assert_equal(y[0], y_0)