Non-negative results when solving a set of equations

[Francesco Potorti`]

>> 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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