2008/5/18, June Kim <[EMAIL PROTECTED]>: > Is there a more efficient way of getting sparse matrix from index/value pairs? > > s > 0 1 │ 1 > 0 2 │ 10 > 1 0 │ 2 > 1 3 │ 100 > (4&$.,.5&$.)s > 0 1 1 > 0 2 10 > 1 0 2 > 1 3 100 > > I'm thinking about some verb f that might satisfy(or something similar): > > s-:(4&$.,.5&$.)s
Sorry for my typo: s-:f (4&$.,.5&$.)s > > I can do that using amend, but I have to build up a blank matrix of I mean, build a blank non-sparse matrix and amend it, and turn it into a sparse matrix. > the full shape in the first place. Are there more efficient ways in > time and space-wise? >
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