Add unsqueeze1d to TH

Unsqueeze inserts a singleton dimension. Unlike view, it doesn't require the tensor to be contiguous.

Author: colesbury

generic/THTensor.c

@@ -510,6 +510,33 @@ void THTensor_(squeeze1d)(THTensor *self, THTensor *src, int dimension)
  }
 }
 
+void THTensor_(unsqueeze1d)(THTensor *self, THTensor *src, int dimension)
+{
+ int d;
+
+ if(!src)
+ src = self;
+
+ THArgCheck((dimension >= 0) && (dimension <= src->nDimension), 2, "dimension out of range");
+ THArgCheck(src->nDimension > 0, 2, "cannot unsqueeze empty tensor");
+
+ THTensor_(set)(self, src);
+
+ self->size = (long*)THRealloc(self->size, sizeof(long)*(self->nDimension+1));
+ self->stride = (long*)THRealloc(self->stride, sizeof(long)*(self->nDimension+1));
+ self->nDimension++;
+ for (d = self->nDimension-1; d > dimension; d--) {
+ self->size[d] = self->size[d-1];
+ self->stride[d] = self->stride[d-1];
+ }
+ if (dimension+1 < self->nDimension) {
+ self->stride[dimension] = self->size[dimension+1] * self->stride[dimension+1];
+ } else {
+ self->stride[dimension] = 1;
+ }
+ self->size[dimension] = 1;
+}
+
 int THTensor_(isContiguous)(const THTensor *self)
 {
  long z = 1;

generic/THTensor.h

@@ -101,6 +101,7 @@ TH_API void THTensor_(unfold)(THTensor *self, THTensor *src, int dimension_, lon
 
 TH_API void THTensor_(squeeze)(THTensor *self, THTensor *src);
 TH_API void THTensor_(squeeze1d)(THTensor *self, THTensor *src, int dimension_);
+TH_API void THTensor_(unsqueeze1d)(THTensor *self, THTensor *src, int dimension_);
 
 TH_API int THTensor_(isContiguous)(const THTensor *self);
 TH_API int THTensor_(isSameSizeAs)(const THTensor *self, const THTensor *src);