josdejong/mathjs

Better documentation of usolve limitations, or possibly error message when input is not upper triangular?

オープン

#2,333 opened on 2021/10/06

 (4 件のコメント) (0 件のリアクション) (0 人の担当者)JavaScript (1,314 件のフォーク)batch import
documentationfeaturehelp wanted

Repository metrics

Stars
 (15,065 個のスター)
PR merge metrics
 (PR metrics pending)

説明

Minimal code:

window.onload = function() {
	const U = math.matrix([[0.10452846326765346,-120],[-0.9945218953682733,-0]])
	const b = math.matrix([-22.163070207475485, -59.419761706007094])

	result = math.usolve(U,b)
	console.log(result)	
}

The error I get: Uncaught Error: Linear system cannot be solved since matrix is singular.

I entered the very same equation into GNU Octave which was able to solve it: it is no unsolvable system. When switching the lines, it even becomes an upper triangular matrix with nonzero values on the diagonal line. So its determinant is not zero, which implicates that the matrix is not even singular!

コントリビューターガイド