Hello, I was curious how long it would take my laptop to solve Ax = b for square A as a function of the problem size. I tried to profile it using BenchmarkTools: ns = [1,2,3,5,7,10,20,30,50,70,100,200,300,500,700,1000,2000,3000,5000,7000,10000] ts = Array{Float64}(undef, length(ns)) for (i,n) in e…

[image] tawheeler: Is it actually using multiple threads under the hood? I think this is just using BLAS so unless you set BLAS threads to 1 it’s probably multi threaded.

Why would A \ b grow with O(n^2)?

Specific Domains Numerics

Elrod November 11, 2023, 6:10pm 4

The cost is probably dominated by lu, which in practice scales much better than O(N^3) up to extremely large sizes.

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Why would A \ b grow with O(n^2)?

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