Function: algsqr
Section: algebras
C-Name: algsqr
Prototype: DGG
Help: algsqr({al},x): element x^2 in al (Hamilton quaternions if omitted).
Doc: Given an element $x$ in \var{al} (Hamilton quaternions if omitted),
 computes its square $x^{2}$ in the algebra \var{al}.
 \bprog
 ? A = alginit(nfinit(y), [-1,-1]);
 ? algsqr(A,[1,0,2,0]~)
 %2 = [-3, 0, 4, 0]~
 ? algsqr(,[0,0,0,Pi]~) \\ Hamilton quaternions
 %3 = [-9.8696044010, 0, 0, 0]~
 @eprog

 Also accepts a square matrix with coefficients in \var{al}.
