Function: quadpoly
Section: number_theoretical
C-Name: quadpoly0
Prototype: GDn
Help: quadpoly(D,{v='x}): quadratic polynomial corresponding to the
 discriminant D, in variable v.
Doc: creates the ``canonical'' quadratic
 polynomial (in the variable $v$) corresponding to the discriminant $D$,
 i.e.~the minimal polynomial of $\kbd{quadgen}(D)$. $D$ must be an integer
 congruent to 0 or 1 modulo 4, which is not a square.

 \bprog
 ? quadpoly(5,'y)
 %1 = y^2 - y - 1
 ? quadpoly(0,'y)
  ***   at top-level: quadpoly(0,'y)
  ***                 ^--------------
  *** quadpoly: domain error in quadpoly: issquare(disc) = 1
 @eprog
