fixing corner-case of last dimension in addSingletonDimension

1 files changed, 2 insertions, 1 deletions

diff --git a/utils.lua b/utils.lua
index 4d89568..40cc377 100644
--- a/utils.lua
+++ b/utils.lua
@@ -68,7 +68,8 @@ end
 function nn.utils.addSingletonDimension(t, dim)
   assert(torch.isTensor(t), "input tensor expected")
   local dim = dim or 1
-  assert(dim > 0 and dim <= t:dim(), "invalid dimension: " .. dim)
+  assert(dim > 0 and dim <= (t:dim() + 1), "invalid dimension: " .. dim
+             .. '. Tensor is of ' .. t:dim() .. ' dimensions.')
 
   local view = t.new()
   local size = torch.LongStorage(t:dim() + 1)