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Re: Non-negative results when solving a set of equations
From: |
Francesco Potorti` |
Subject: |
Re: Non-negative results when solving a set of equations |
Date: |
Thu, 05 Jun 2008 08:43:35 +0200 |
>> I have a set of equations (Ax = b) that I can solve with A\b.
>> However, due to physical reasons, the result can not contain negative values
>> (they should be zero in that case). I went through the manual and did a
>> search, but found nothing that could help me.
That depends on what you want. If you want to "solve" the equations,
there is nothing to do, because you hav a single solution, provided that
A is non-singular.
If you want simply to set negative values to zero, you do:
x=A\b; x(x<0)=0;
>If you are not satisfied with simply setting the negative components of
>the solution to zero, look for function lsqnonneg.
Interesting. Is there a free implementation for Octave?
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