Solve with a vector of coefficients

I want to obain the positive roots or a polynomial like

fun= x^3+ A*x^2 + B *x + D==0

h = single(solve(fun,x));

h=h(h>0);

Both A and B coefs are function of the same parameter (V)

A= vb/2

b=vb^2

and vb is defined as a vector

vb= linspace(0,100,101)

I want to obtain a vector (p)with the solutions in ordet to plot

plot (vb,p)

I've tried with loops (for and while) but both are too slow.

There is another way to do that?

Answer 1

[Stephan]

Hi,

if i assume that you do not do symbolic calculations and you have values for D, then for this purpose there is the roots function, which should be much faster than solve in this case.

Best regards

Stephan

[Rafael Ibáñez]

Solved.

Thank you