josdejong/mathjs

Kronecker product needs a SparseMatrix implementation

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#1,610 opened on Sep 6, 2019

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featurehelp wanted

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Description

The current implementation of the Kronecker product #704 silently changes sparse matrices into dense matrices.

Example:

v1 = math.matrix([0, 2, 3, 0, 0], 'sparse')
v2 = math.matrix([0, 1, 0 -1], 'sparse')
v = math.kron(v1, v2)

Returns v, which is a DenseMatrix even though v1 and v2 areSparseMatrix. I would expect SparseMatrix instead.

Is it intended behavior?

Contributor guide

Research direction
Inspect the kron function in the math library, identify where dense matrix conversion occurs, and add sparse matrix support for the Kronecker product.
Tech stack
javascript
Domain
data
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
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Active
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Clear
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JavaScriptGit
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75