DEFINITION MODULE Elliptic;

   (*  EXPORT QUALIFIED El2, CEl, SnCnDn; *)

   PROCEDURE El2(x, qqc, aa, bb: REAL): REAL; 
   (*
     Returns the general elliptic integral of the second kind,
     el2(x,kc,a,b) with x=x>= 0, qqc=kc, aa=a, and bb=b.
   *)

   PROCEDURE CEl(qqc, pp, aa, bb: REAL): REAL; 
   (*
     Returns the general complete elliptic integral cel(kc,p,a,b)
     with qqc=kc, pp=p, aa=a, and bb=b.
   *)

   PROCEDURE SnCnDn(    uu, emmc: REAL; 
                    VAR sn, cn, dn: REAL); 
   (*
     Returns the Jacobian elliptic functions sn(u,kc), cn(u,kc)
     and dn(u,kc). Here uu=u, while emmc=kc^2.
   *)

END Elliptic.