Each element of the tensor other is multiplied by the scalar
alpha and added to each element of the tensor input.
The resulting tensor is returned.
The shapes of input and other must be
broadcastable .
$$
\mbox{out} = \mbox{input} + \mbox{alpha} \times \mbox{other}
$$
If other is of type FloatTensor or DoubleTensor, alpha must be
a real number, otherwise it should be an integer.