Re: Leasqr matrix singular to machine precision

[Francesco Potorti`]

>As I could not solve the system I was asking why and found from the 
>example leasqrdemo that I can give more points than the number of 
>unknown (an overestimated system is possible !). 

Sure it is possible!  That is the whole point of least square
optimization.

>If I try to modify the inital guess it doesn't converge and arrive to 
>imaginary values...

Try with more points, and with different initial guesses.  Try with a
simpler problem, and change it gradually.  Try to start with something
that you know has a solution.

>Now I need help ! Does 4 variables are too much ? 

Definitely not.

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