I have a index matrix and a matrix filled by zero .
For example :
index = Tensor([[ 0,  1],
                [ 1,  2],
                [ 4,  1]])
a = Tensor([[ 0.,  0.,  0.,  0.,  0.,  0.],
            [ 0.,  0.,  0.,  0.,  0.,  0.],
            [ 0.,  0.,  0.,  0.,  0.,  0.]])

Therefore, I would like to fill 1 to the zero matrix based on the index matrix .
Like this :
a = Tensor([[ 1,  1,  0,  0.,  0.,  0.],
            [ 0.,  1,  1,  0.,  0.,  0.],
            [ 0.,  1,  0.,  0.,  1,  0.]])

Is there any easy way ?