Advice for rank computation

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Charles Bouillaguet

Apr 12, 2016, 4:26:00 PM4/12/16
to ffpack-devel
Hi guys,

I would like to use FFLAS-FFPACK to compute the rank of a dense matrix. The coefficients are integer modulo 42013 (not centered around zero), stored inside int32_t. I will thus have row vectors of type int32_t[].

My code produces the matrix row-by-row. It looks like this :

int32_t row = malloc(...)
for(i=0; i<n; i++) {
    [code that fills row]
    <insert FFLAS magic here>
int k = FFPACK::Rank(.....)

What is the best way to build the FFLAS matrix object, and which field implementation should I use? Can I use level-2 "assign" operations with my row vectors?

Thanks to all of you,
Charles Bouillaguet

Jean-Guillaume Dumas

Apr 14, 2016, 5:48:54 AM4/14/16
I would recommend ModularBalanced<double> anyway ,
then use a level2 finit to convert to the centered representation.

there is no explicit init from int32, but there is one from int64.
So either conversion wil work smoothly, or one need to add one in

inline ModularBalanced<double>::Element&
ModularBalanced<double>::init(Element& x, const int32_t y) const


Jean-Guillaume Dumas.
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