Fix vstack (#45)

* Fix vstack

The numpy API now requires a sequence rather than an iterator so wrap in list before passing to `vstack`

* Update test_api.py

The numpy test utils moved

cis/collocation/data_index.py

@@ -77,11 +77,11 @@ def index_data(self, coords, hyper_points, coord_map):
         # Output is a list of coordinates which lists the indexes where the hyper points
         #    should be located in the grid
         indices = np.vstack(
-            np.where(
-                ci < max_coordinate_value,
-                np.searchsorted(bi, ci, side='right') - 1,
-                -1)
-            for bi, ci, max_coordinate_value in bounds_coords_max)
+            [np.where(
+                 ci < max_coordinate_value,
+                 np.searchsorted(bi, ci, side='right') - 1,
+                 -1)
+             for bi, ci, max_coordinate_value in bounds_coords_max])
 
         # D-tuple giving the shape of the output grid
         grid_shape = tuple(len(bi_ci[0]) for bi_ci in bounds_coords_max)

cis/test/unit/test_api.py

@@ -6,7 +6,7 @@
 from cis.test.util.mock import make_mock_cube, make_regular_2d_ungridded_data
 from cis.data_io.gridded_data import make_from_cube
 import numpy as np
-from numpy.testing.utils import assert_array_almost_equal
+from numpy.testing import assert_array_almost_equal
 
 
 class TestAPI(TestCase):