Matlab polyfit to Yalmip

[Paras Salunkhe]

Hi,

 I have a polynomial generated in Matlab using the polyfit command. I want to convert this polynomial as a sdpvar polynomial. Any way how I can do that?

Thanks,

-Paras

[Johan Löfberg]

No direct command, but with the coefficients, it is just straightforward coding, vectorized or what ever you want to do

X = 0:0.1:1;Y = sin(X);
c = polyfit(X,Y,3);
p = fliplr(c)*monolist(x,3);
p = c*(x.^(3:-1:0)');
p = 0;for i = 0:3;p = p + c(i+1)*x.^(3-i);end
sdisplay(p)
-0.000133237237+1.0042*x-0.0188*x^2-0.1440*x^3

[Mark L. Stone]

You have a typo in the final method.  Should be c(i+1), not c(i) .

[Johan Löfberg]

Right, thanks