determ

Scilab Function
Last update : 09/06/2006

determ - determinant of polynomial matrix

### Calling Sequence

  `res=determ(W [,k])`

### Parameters

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

### Description

returns the determinant of a real polynomial matrix (computation made by FFT if W size is greater than 2*2).

`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 (Only if W size is greater than 2*2) : evaluate the determinant of `W` for the Fourier frequencies and apply inverse FFT to the coefficients of the determinant.

### Examples

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

### See Also

`det` , `detr` , `coffg` ,

### Author

F.D.