Sorry for asking but could you elaborate more on this?
I don’t understand the index part!?
Update :
I guess I understood it thanks to God!
0, 1, 2, 0 , 0 are the row indexes of our destination tensor .
this simply means, put the first element from source into the first row  of  the destination tensor (at the same exact index )
so 0th element in x which is 0.3992 goes to row 0. and in index 0.
1tst element in x which is 0.2908 goes to row 1 and in index 1
2nd element in x which is 0.9044 will go to row 2 and in index 2
3rd element in x which is 0.4850 will go to row 0 and in index 3
4th element in x which is ’ 0.6004 will go to row 0 and in index 4
and this goes on.
Basically, all elements in source will have their respective index, but they only are redirected to a specific row in the destination tensor!
Is this right?