diff --git a/mistree/tests/test_coordinates.py b/mistree/tests/test_coordinates.py
index 9a2cb8f..e29ec51 100644
--- a/mistree/tests/test_coordinates.py
+++ b/mistree/tests/test_coordinates.py
@@ -4,24 +4,24 @@
 
 def test_spherical_2_cartesian():
     x, y, z = mist.spherical_2_cartesian(1., 0., 0.)
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     x, y, z = mist.spherical_2_cartesian(1., 90., 90.)
     assert round(x, 6) == 0.
-    assert y == 1.
+    assert round(y, 6) == 1.
     assert round(z, 6) == 0.
     x, y, z = mist.spherical_2_cartesian(1., 90., 45.)
     assert round(x, 6) == 0.
     assert round(y, 6) == round(1./np.sqrt(2.), 6)
     assert round(z, 6) == round(1./np.sqrt(2.), 6)
     x, y, z = mist.spherical_2_cartesian(1., 0., 0., units='radians')
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     x, y, z = mist.spherical_2_cartesian(1., np.pi/2., np.pi/2., units='radians')
     assert round(x, 6) == 0.
-    assert y == 1.
+    assert round(y, 6) == 1.
     assert round(z, 6) == 0.
     x, y, z = mist.spherical_2_cartesian(1., np.pi/2., np.pi/4., units='radians')
     assert round(x, 6) == 0.
@@ -43,64 +43,64 @@ def test_celestial_2_cartesian():
     p = mist.celestial_2_cartesian(1., 0., 0., output='spherical')
     assert len(p) == 2
     phi, theta, x, y, z = mist.celestial_2_cartesian(1., 0., 90.)
-    assert phi == 0.
-    assert theta == 0.
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(phi, 6) == 0.
+    assert round(theta, 6) == 0.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     x, y, z = mist.celestial_2_cartesian(1., 0., 90., output='cartesian')
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     phi, theta, x, y, z = mist.celestial_2_cartesian(1., 0., 0.)
-    assert phi == 0.
+    assert round(phi, 6) == 0.
     assert round(theta, 6) == round(np.pi/2., 6)
-    assert x == 1.
-    assert y == 0.
+    assert round(x, 6) == 1.
+    assert round(y, 6) == 0.
     assert round(z, 6) == 0.
     x, y, z = mist.celestial_2_cartesian(1., 0., 0., output='cartesian')
-    assert x == 1.
-    assert y == 0.
+    assert round(x, 6) == 1.
+    assert round(y, 6) == 0.
     assert round(z, 6) == 0.
     phi, theta, x, y, z = mist.celestial_2_cartesian(1., 0., 45.)
-    assert phi == 0.
+    assert round(phi, 6) == 0.
     assert round(theta, 6) == round(np.pi/4., 6)
     assert round(x, 6) == round(np.sqrt(2.)/2., 6)
-    assert y == 0.
+    assert round(y, 6) == 0.
     assert round(z, 6) == round(np.sqrt(2.)/2., 6)
     x, y, z = mist.celestial_2_cartesian(1., 0., 45., output='cartesian')
     assert round(x, 6) == round(np.sqrt(2.)/2., 6)
-    assert y == 0.
+    assert round(y, 6) == 0.
     assert round(z, 6) == round(np.sqrt(2.)/2., 6)
     phi, theta, x, y, z = mist.celestial_2_cartesian(1., 0., np.pi/2., units='radians')
-    assert phi == 0.
-    assert theta == 0.
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(phi, 6) == 0.
+    assert round(theta, 6) == 0.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     x, y, z = mist.celestial_2_cartesian(1., 0., np.pi/2., output='cartesian', units='radians')
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     phi, theta, x, y, z = mist.celestial_2_cartesian(1., 0., 0., units='radians')
-    assert phi == 0.
+    assert round(phi, 6) == 0.
     assert round(theta, 6) == round(np.pi/2., 6)
-    assert x == 1.
-    assert y == 0.
+    assert round(x, 6) == 1.
+    assert round(y, 6) == 0.
     assert round(z, 6) == 0.
     x, y, z = mist.celestial_2_cartesian(1., 0., 0., output='cartesian', units='radians')
-    assert x == 1.
-    assert y == 0.
+    assert round(x, 6) == 1.
+    assert round(y, 6) == 0.
     assert round(z, 6) == 0.
     phi, theta, x, y, z = mist.celestial_2_cartesian(1., 0., np.pi/4., units='radians')
-    assert phi == 0.
+    assert round(phi, 6) == 0.
     assert round(theta, 6) == round(np.pi/4., 6)
     assert round(x, 6) == round(np.sqrt(2.)/2., 6)
-    assert y == 0.
+    assert round(y, 6) == 0.
     assert round(z, 6) == round(np.sqrt(2.)/2., 6)
     x, y, z = mist.celestial_2_cartesian(1., 0., np.pi/4., output='cartesian', units='radians')
     assert round(x, 6) == round(np.sqrt(2.)/2., 6)
-    assert y == 0.
+    assert round(y, 6) == 0.
     assert round(z, 6) == round(np.sqrt(2.)/2., 6)
     phi, theta, x, y, z = mist.celestial_2_cartesian(np.random.random_sample(100),
                                                      360.*np.random.random_sample(100),
@@ -114,35 +114,35 @@ def test_celestial_2_cartesian():
 
 def test_spherical_2_unit_sphere():
     x, y, z = mist.spherical_2_unit_sphere(0., 0.)
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     x, y, z = mist.spherical_2_unit_sphere(0., 90.)
-    assert x == 1.
-    assert y == 0.
+    assert round(x, 6) == 1.
+    assert round(y, 6) == 0.
     assert round(z, 6) == 0.
     x, y, z = mist.spherical_2_unit_sphere(90., 90.)
     assert round(x, 6) == 0.
-    assert y == 1.
+    assert round(y, 6) == 1.
     assert round(z, 6) == 0.
     x, y, z = mist.spherical_2_unit_sphere(45., 45.)
     assert round(x, 6) == 0.5
     assert round(y, 6) == 0.5
     assert round(z, 6) == round(np.sqrt(2.)/2., 6)
     x, y, z = mist.spherical_2_unit_sphere(0., 0., units='radians')
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     x, y, z = mist.spherical_2_unit_sphere(0., np.pi/2., units='radians')
-    assert x == 1.
-    assert y == 0.
+    assert round(x, 6) == 1.
+    assert round(y, 6) == 0.
     assert round(z, 6) == 0.
     x, y, z = mist.spherical_2_unit_sphere(np.pi/2., np.pi/2., units='radians')
     assert round(x, 6) == 0.
-    assert y == 1.
+    assert round(y, 6) == 1.
     assert round(z, 6) == 0.
     x, y, z = mist.spherical_2_unit_sphere(np.pi/4., np.pi/4., units='radians')
-    assert x == 0.5
+    assert round(x, 6) == 0.5
     assert round(y, 6) == 0.5
     assert round(z, 6) == round(np.sqrt(2.)/2., 6)
     x, y, z = mist.spherical_2_unit_sphere(180.*np.random.random_sample(100), 360.*np.random.random_sample(100))
@@ -156,64 +156,64 @@ def test_celestial_2_unit_sphere():
     p = mist.celestial_2_unit_sphere(0., 0., output='cartesian')
     assert len(p) == 3
     phi, theta, x, y, z = mist.celestial_2_unit_sphere(0., 90.)
-    assert phi == 0.
-    assert theta == 0.
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(phi, 6) == 0.
+    assert round(theta, 6) == 0.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     x, y, z = mist.celestial_2_unit_sphere(0., 90., output='cartesian')
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     phi, theta, x, y, z = mist.celestial_2_unit_sphere(0., 0.)
-    assert phi == 0.
+    assert round(phi, 6) == 0.
     assert round(theta, 6) == round(np.pi/2., 6)
-    assert x == 1.
-    assert y == 0.
+    assert round(x, 6) == 1.
+    assert round(y, 6) == 0.
     assert round(z, 6) == 0.
     x, y, z = mist.celestial_2_unit_sphere(0., 0., output='cartesian')
-    assert x == 1.
-    assert y == 0.
+    assert round(x, 6) == 1.
+    assert round(y, 6) == 0.
     assert round(z, 6) == 0.
     phi, theta, x, y, z = mist.celestial_2_unit_sphere(0., 45.)
-    assert phi == 0.
+    assert round(phi, 6) == 0.
     assert round(theta, 6) == round(np.pi/4., 6)
     assert round(x, 6) == round(np.sqrt(2.)/2., 6)
-    assert y == 0.
+    assert round(y, 6) == 0.
     assert round(z, 6) == round(np.sqrt(2.)/2., 6)
     x, y, z = mist.celestial_2_unit_sphere(0., 45., output='cartesian')
     assert round(x, 6) == round(np.sqrt(2.)/2., 6)
-    assert y == 0.
+    assert round(y, 6) == 0.
     assert round(z, 6) == round(np.sqrt(2.)/2., 6)
     phi, theta, x, y, z = mist.celestial_2_unit_sphere(0., np.pi/2., units='radians')
-    assert phi == 0.
-    assert theta == 0.
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(phi, 6) == 0.
+    assert round(theta, 6) == 0.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     x, y, z = mist.celestial_2_unit_sphere(0., np.pi/2., output='cartesian', units='radians')
-    assert x == 0.
-    assert y == 0.
-    assert z == 1.
+    assert round(x, 6) == 0.
+    assert round(y, 6) == 0.
+    assert round(z, 6) == 1.
     phi, theta, x, y, z = mist.celestial_2_unit_sphere(0., 0., units='radians')
-    assert phi == 0.
+    assert round(phi, 6) == 0.
     assert round(theta, 6) == round(np.pi/2., 6)
-    assert x == 1.
-    assert y == 0.
+    assert round(x, 6) == 1.
+    assert round(y, 6) == 0.
     assert round(z, 6) == 0.
     x, y, z = mist.celestial_2_unit_sphere(0., 0., output='cartesian', units='radians')
-    assert x == 1.
-    assert y == 0.
+    assert round(x, 6) == 1.
+    assert round(y, 6) == 0.
     assert round(z, 6) == 0.
     phi, theta, x, y, z = mist.celestial_2_unit_sphere(0., np.pi/4., units='radians')
-    assert phi == 0.
+    assert round(phi, 6) == 0.
     assert round(theta, 6) == round(np.pi/4., 6)
     assert round(x, 6) == round(np.sqrt(2.)/2., 6)
-    assert y == 0.
+    assert round(y, 6) == 0.
     assert round(z, 6) == round(np.sqrt(2.)/2., 6)
     x, y, z = mist.celestial_2_unit_sphere(0., np.pi/4., output='cartesian', units='radians')
     assert round(x, 6) == round(np.sqrt(2.)/2., 6)
-    assert y == 0.
+    assert round(y, 6) == 0.
     assert round(z, 6) == round(np.sqrt(2.)/2., 6)
     phi, theta, x, y, z = mist.celestial_2_unit_sphere(360.*np.random.random_sample(100),
                                                        180.*np.random.random_sample(100) - 90.)