varn

varn — symbolic variable of a polynomial

Calling sequence

[symb]=varn(p)  
[pm]=varn(x,var)

`p`	: polynomial (or matrix polynomial)
`symb`	: character string
`x`	: polynomial or polynomial matrix
`var`	: symbolic variable (character string)
`pm`	: matrix or polynomial matrix

symb=varn(p) returns in symb the symbolic variable of the polynomial p (i.e. varn(poly(0,'x')) is 'x').

varn(x,'s') returns a polynomial matrix with same coefficients as x but with 's' as symbolic variable (change of variable name).



// 
s=poly(0,'s');p=[s^2+1,s];
varn(p)
varn(p,'x')