determ

determ — determinant of polynomial matrix

Calling sequence

res=determ(W [,k])

`W`	: real square polynomial matrix
`k`	: integer (upper bound for the degree of the determinant of W)

returns the determinant of a real polynomial matrix (computation made by FFT).

res=determ(W [,k])k is an integer larger than the actual degree of the determinant of W.

The default value of k is the smallest power of 2 which is larger than n*maxi(degree(W)).

Method: evaluate the determinant of W for the Fourier frequencies and apply inverse FFT to the coefficients of the determinant.



s=poly(0,'s');
w=s*rand(10,10);
determ(w)
det(coeff(w,1))*s^10

F.D.