It seems converting a Q matrix to a Float Matrix takes high-degree polynomial time at best. Is this a bug? If so, is there any way to work around it? I don’t remember having this problem on earlier versions (I am using 1.01). Granted my laptop is pretty slow, but this is worse than matrix inversion…

RalphAS on the GitHub issue thread ( # 29846 ) noted that we can drop the type parameter and recover performance, e.g. writing Matrix{Float64}(f.Q). This workaround fixed the slowness in my code, so I will count the question as solved.

QR Decomposition Extremely Slow

General Usage

jpsamaroo October 30, 2018, 2:26am 3

1 Like

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QR Decomposition Extremely Slow

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