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Subject: Re: [ublas] Element-wise operations are really slow
From: Vardan Akopian (vakopian_at_[hidden])
Date: 2010-04-22 15:43:01

On Thu, Apr 22, 2010 at 10:26 AM, xiss burg <xissburg_at_[hidden]> wrote:

> Vardan,
> I get the same performance with double precision. I have NDEBUG defined,
> but I don't know about other optimization flags. I didn't profile with any
> tool but the bottle neck is exactly at that section of the code where I
> perform the element wise summation. I'll try to make a simple sample which
> performs the same kind of operations to see what I get.

My point wasn't really about float vs double, but rather matrix<float> vs
compressed_matrix<float> (or the other types you've tried).
The ublas matrix<float>, with proper inlining, should have next to 0 impact
(all it does is calculate an offset into the storage).
So if you're seeing bad performance even with matrix<float>, then it's
definitely not a problem with matrix element access.