Merge pull request #2167 from abergeron/blocksparse_doc

theano/sandbox/cuda/blocksparse.py

@@ -18,6 +18,13 @@ class SparseBlockGemvSS(GpuOp):
     This op computes the dot product of specified pieces of vectors
     and matrices, returning pieces of vectors.
 
+    It computes something like this for each j:
+
+      o[j] = sum_over_i(dot(W[i, j], h[i])) + o[j]
+
+    The i and j are taken from the inputIdx and outputIdx lists
+    respectively.
+
     This should not be directly called since the interface is subject
     to change without notice.  Use the sparse_block_dot_SS() function
     for a stable interface.
@@ -343,6 +350,12 @@ class SparseBlockOuterSS(GpuOp):
     This computes the outer product of two sets of pieces of vectors
     updating a full matrix with the results.
 
+    It computes something like this:
+
+      o[i, j] = (alpha * outer(x[i], y[j])) + o[i, j]
+
+    The i and j are taken from the xIdx and yIdx lists respectively.
+
     This op should not be called directly since its interface is
     subject to change without notice.  It is involved in the gradient
     of SparseBlockGemvSS.