How can I get the degree of a polynomial defined symbolically in MATLAB?

I defined a polynomial of several variables symbolically as follows: 

 

       syms x y z
       P = x^4 + 3*x^2*y^2 - z^3 + y + 1

 

I can get the coefficients of the polynomial using the "coeffs" function. Now I would like to get the exponents of the polynomial but I can't seem to find a function to do that. 

 

Is there a way to get the degree of a polynomial in the Symbolic Math Toolbox R2013b? I don't want to use a MuPAD notebook because all my code is written in MATLAB functions.

Answer 1

[MathWorks Support Team]

As of release R2014a, there is no MATLAB function in the Symbolic Math Toolbox that can get the degree of a polynomial defined symbolically.

As a workaround you can use the MuPAD function "degree". To call the MuPAD engine from within MATLAB in order to use "degree", use the "feval" function as follows:

>> syms x y z
>> P = x^4 + 3*x^2*y^2 - z^3 + y + 1;
>> feval(symengine, 'degree', P)

ans =

4

To get the degree of "P" with respect to a specific variable, use the following:

>> syms x y z
>> P = x^4 + 3*x^2*y^2 - z^3 + y + 1;
>> feval(symengine, 'degree', P, y)

ans =

2