pytorch中矩阵与向量的加/减

Question

我想在pytorch的矩阵和向量之间做~/-/*。 我怎样才能有好的表现呢？ 我试着使用expand，但是它非常慢（我使用的是带小向量的大矩阵）。

a = torch.rand(2,3)
print(a)
 0.7420  0.2990  0.3896
 0.0715  0.6719  0.0602
[torch.FloatTensor of size 2x3]
b = torch.rand(2)
print(b)
 0.3773
 0.6757
[torch.FloatTensor of size 2]
a.add(b)
Traceback (most recent call last):
  File "C:\ProgramData\Anaconda3\lib\site-packages\IPython\core\interactiveshell.py", line 3066, in run_code
    exec(code_obj, self.user_global_ns, self.user_ns)
  File "<ipython-input-17-a1cb1b03d031>", line 1, in <module>
    a.add(b)
RuntimeError: inconsistent tensor size, expected r_ [2 x 3], t [2 x 3] and src [2] to have the same number of elements, but got 6, 6 and 2 elements respectively at c:\miniconda2\conda-bld\pytorch-cpu_1519449358620\work\torch\lib\th\generic/THTensorMath.c:1021

预期结果：

 0.7420-0.3773  0.2990-0.3773  0.3896-0.3773
 0.0715-0.6757  0.6719-0.6757  0.0602-0.6757