fix travis fail
@@ -581,7 +581,7 @@ def test_stack(geom, geom_etrue):
dataset1.stack(dataset2)
assert_allclose(dataset1.counts.data.sum(), 7987)
assert_allclose(dataset1.background_model.map.data.sum(), 5987)
- assert_allclose(dataset1.exposure.data, 293509914234325.9)
+ assert_allclose(dataset1.exposure.data.sum(), 293509914234325.9)
assert_allclose(dataset1.mask_safe.data.sum(), 20000)
assert len(dataset1.models) == 1
