| Re: [eigen] Eigen 3 is extremely slow |
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] Eigen 3 is extremely slow
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Mon, 14 Mar 2011 09:18:34 -0400
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2011/3/14 Gael Guennebaud <gael.guennebaud@xxxxxxxxx>:
> On Mon, Mar 14, 2011 at 12:48 AM, Hari Sundar <hsundar@xxxxxxxxx> wrote:
>> For example a simple 4x4 * 4*1 multiplication takes around 0.5msec.
>
> hm, that's indeed extremely slow... which compiler? flags?
>
> for instance here a 4x4 * 4x1 product takes less than 4e-6msec, and
> even in debug mode (-g2) with a very old gcc 3.4 it takes less than
> 0.0008 msec...
If his matrix has NaN values, that could explain another 500x factor.
Benoit
>
> gael
>
>
>