How to use index array to replace values present at indices with a number

[Prabakaran-Chandran]

I have indices in an array , say Index_array = [[0,1] , [1,2] , [2,3]]

how to use this array for math.subset function .

math.subset(array , math.index(Index_array) , 1) is not working

Please help me

[josdejong]

Have you seen the docs and examples on how to use indexes, Prabakaran?

See: https://mathjs.org/docs/datatypes/matrices.html#getting-or-replacing-subsets