如何从 torch/lua 中的大矩阵中提取矩阵

Question

在 torch7 / lua

有一个矩阵：

[  1,  2,  3,  4;
   5,  6,  7,  8;
   9, 10, 11, 12;
  13, 14, 15, 16  ]

如何提取：

[  6,  7;
  10, 11  ]

以及如何用矩阵运算覆盖

[  1,  2,  3,  4;
   5, 78, 66,  8;
   9, 45, 21, 12;
  13, 14, 15, 16  ]

提前致谢。

Answer 1

matrix

matrix:sub(2,3,2,3)

z = torch.Tensor({{78,66},{45,21}})

matrix:sub(2,3,2,3):copy(z)

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