gcd of polynomials
[pg,U]=hrmt(v)
:v row of polynomials i.e. 1`x `k polynomial matrix : :pg polynomial : :U unimodular matrix polynomial :
[pg,U]=hrmt(v) returns a unimodular matrix U and pg = gcd of row of polynomials v such that v*U = [pg,0].
x=`poly`_(0,'x');
v=[x*(x+1),x^2*(x+1),(x-2)*(x+1),(3*x^2+2)*(x+1)];
[pg,U]=hrmt(v);U=`clean`_(U)
`det`_(U)