function [num,den] = pdet(A)

% PDET  Determinant of matrices with polynomial entries.
%       [num,den] = PDET(A) returns the numerator and the denominator
%	of the determinant of the square matrix of polynomials A.

%	Written by Serge Tchikanda 06/20/96.
%       Last revised by Serge Tchikanda 06/24/96.

[m,n] = psize(A);

if (isempty(m)) | (isempty(n)) | (m ~= n)
   disp(' ')
   disp('   Matrix must be square.')
   return
end

A = pquick(A);
[num1,den1] = gpet(A,1:m,1:n);

num = 1;
den = 1;
for i = 1:m
    num = conv(num1(i,:),num);
    den = den*den1;
end

num = delzeros(num);
g = matgcd([num den]);
if g ~= 0
   num = num/g;
   den = den/g;
end