PyTorch获取二维张量中的值的索引

时间:2020-01-25 10:38:38

标签: python pytorch tensor

给出以下张量(或任何二维的随机张量),我想得到'101'的索引:

tens = tensor([[  101,   146,  1176, 21806,  1116,  1105, 18621,   119,   102,     0,
             0,     0,     0],
        [  101,  1192,  1132,  1136,  1184,   146,  1354,  1128,  1127,   117,
          1463,   119,   102],
        [  101,  6816,  1905,  1132, 14918,   119,   102,     0,     0,     0,
             0,     0,     0]])

从相关答案中,我知道我可以做这样的事情:

idxs = torch.tensor([(i == 101).nonzero() for i in tens])

但是,这似乎很混乱,并且可能非常缓慢。有没有更好的方法来做到这一点,而且又更快呢?

仅讨论一维张量的相关问题:

1 个答案:

答案 0 :(得分:2)

(tens == 101).nonzero()[:, 1]

In [20]: from torch import tensor                                                                       

In [21]: tens = torch.tensor([[  101,   146,  1176, 21806,  1116,  1105, 18621,   119,   102,     0, 
    ...:              0,     0,     0], 
    ...:         [  101,  1192,  1132,  1136,  1184,   146,  1354,  1128,  1127,   117, 
    ...:           1463,   119,   102], 
    ...:         [  101,  6816,  1905,  1132, 14918,   119,   102,     0,     0,     0, 
    ...:              0,     0,     0]])                                                                

In [22]: (tens == 101).nonzero()[:, 1]                                                                  
Out[22]: tensor([0, 0, 0])