| Re: [eigen] Machine precision<> too coarse |
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] Machine precision<> too coarse
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Tue, 3 Feb 2009 19:36:06 +0100
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2009/2/3 Keir Mierle <mierle@xxxxxxxxx>:
> Exactly. The user is the one who should make that choice. I have had cases
> where I was working near machine precision, and got slightly innaccurate
> results, but it was fine because I then pushed the values through a
> minimizer.
>
> If the matrix library had set a too-coarse precision then I couldn't have
> done this.
If you want we can allow the LU constructor to take an optional
precision parameter to override the default. That would make sense.
LU<MatrixXd> lu(m, prec);
result = lu.rank();
Benoit