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 I can do that using amend, but I have to build up a blank matrix of the full shape in the first place. Are there more efficient ways in time and space-wise?
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