fixed argchecks
diff --git a/THCTensorMath.cu b/THCTensorMath.cu
index 3d2375f..887d67a 100644
--- a/THCTensorMath.cu
+++ b/THCTensorMath.cu
@@ -1077,7 +1077,8 @@
   long size = THCudaTensor_nElement(data)/data->size[0];
   
   THArgCheck(dimension >= 0 && dimension < THCudaTensor_nDimension(src), 3, "invalid dimension");
-  THArgCheck(value > 0, 3, "non-positive-norm not supported");
+  THArgCheck(value > 0, 2, "non-positive-norm not supported");
+  THArgCheck(THCudaTensor_nDimension(src) > 1, 1, "need at least 2 dimensions");
 
   dim3 grid(data->size[0]);
   dim3 threads(32);