bugfix: properly handle occupancy count with empty prds

The size of the occupancy array was not equal to the number of bins when the last bin didn't
have an image in it. Now it's properly zero padded

This is probably related to #19

ManifoldEM/S2tessellation.py

@@ -17,9 +17,10 @@ def quaternion_to_S2(q):
 
 
 def collect_nearest_neighbors(X, Q):
+    nbins = X.shape[0]
     nbrs = NearestNeighbors(n_neighbors=1, algorithm='ball_tree').fit(X)
-    _, neighb_bins = nbrs.kneighbors(Q)
-    bin_counts = np.bincount(neighb_bins.squeeze())
+    neighb_bins = nbrs.kneighbors(Q, return_distance=False)
+    bin_counts = np.bincount(neighb_bins.squeeze(), minlength=nbins)
     return neighb_bins, bin_counts