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Results tagged with matrix
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user 34651
Questions on the manipulation of matrices in Mathematica.
0
votes
2
answers
225
views
Flipping random elements in a matrix
[A];
lis1 = Most[ArrayRules[A]];
lis2 = RandomChoice[lis1, n] ;
lis2 = Map[ReplacePart[#, 2 -> -2] &, lis2[[1 ;; n]]];
S = SparseArray[lis2, {size[[1]], size[[1]]}, 0] + A ;];
It takes an adjacency matrix … still need to tweak is making sure I the entries are flipped symmetrically, i.e. if the (1,2) entry is picked by RandomChoice then I need to also add the (2,1) entry of lis1 so that S is a symmetric matrix …
- 187
7
votes
2
answers
1k
views
Replacing elements of a matrix
I'm trying to write a program that takes a given matrix A of 1's and 0's and flips a designated amount of 1's to -1's. …
- 187