MATLAB: Unity coefficient in symbolic polinomial

polynomialsymbolic

Hello,
When working with symbolic polynomials, they are always expressed in the form
a_n*s^n+...a_1*s+a_0
is there a way to express the polynomial in the form
a_n*(s^n+...a_1'*s+a_0')
a_i'= a_i/a_n
I would find this useful as I'm working with transfer functions, and with lots of expressions it's time-consuming to make the factorization by hand. Thanks!

Best Answer

This is one approach:
syms x s 
f = 5*x^3 - 3*x^2 + 2*x - 1;
polynrm = @(p,v) vpa(poly2sym(poly(roots(sym2poly(p))), v));
a = polynrm(f,s)
a =
s^3 - 0.6*s^2 + 0.4*s - 0.2
This creates an anonymous function you can use to normalise the polynomials. The first argument is the polynomial, and the second is the variable you want to express it in.
This obviously only works with numeric coefficients. I could not find specific functions, or function options, to do this.
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