remove nan mode, use dimshuffle for outer

theano/gpuarray/linalg.py

@@ -419,8 +419,14 @@ class GpuCublasTriangularSolve(Op):
 
         trans_solve_op = GpuCublasTriangularSolve(not self.lower)
         b_bar = trans_solve_op(A.T, c_bar)
-        A_bar = -tensor.outer(b_bar, c) if c.ndim == 1 else -b_bar.dot(c.T)
 
+        # FIXME: tensor.outer does not appear to use GPU
+        def gpu_outer(x,y):
+            return tensor.dot(x.dimshuffle(0,'x'),y.dimshuffle('x',0))
+
+        A_bar = -gpu_outer(b_bar, c) if c.ndim == 1 else -b_bar.dot(c.T)
+
+        # FIXME: tensor.tril / tensor.triu has no GPU implementation
         if self.lower:
             A_bar = tensor.tril(A_bar)
         else:
@@ -567,15 +573,20 @@ class GpuCholesky(Op):
         dz = gradients[0]
         chol_x = outputs[0]
 
-        ok = ~tensor.any(tensor.isnan(chol_x))
-        chol_x = tensor.switch(ok, chol_x, 1)
-        dz = tensor.switch(ok, dz, 1)
+        # this is for nan mode
+        #
+        # ok = ~tensor.any(tensor.isnan(chol_x))
+        # chol_x = tensor.switch(ok, chol_x, 1)
+        # dz = tensor.switch(ok, dz, 1)
 
         # deal with upper triangular by converting to lower triangular
         if not self.lower:
             chol_x = chol_x.T
             dz = dz.T
 
+        # FIXME: tensor.tril / tensor.triu / tensor.diagonal / tensor.diag
+        # has no GPU implementation
+            
         def tril_and_halve_diagonal(mtx):
             """Extracts lower triangle of square matrix and halves diagonal."""
             return tensor.tril(mtx) - tensor.diag(tensor.diagonal(mtx) / 2.)