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7.5.20.0. Weyl
Procedure from library nctools.lib (see nctools_lib).

Usage:
Weyl()

Return:
ring

Purpose:
create a Weyl algebra structure on the basering

Note:
Activate this ring using the command setring.
Assume the number of variables of a basering is 2k. (if the number of variables is odd, an error message will be returned)
by default, the procedure treats first k variables as coordinates x_i and the last k as differentials d_i
if a non-zero optional argument is given, the procedure treats 2k variables of a basering as k pairs (x_i,d_i), i.e. variables with odd numbers are treated as coordinates and with even numbers as differentials

Example:
 
LIB "nctools.lib";
ring A1=0,(x(1..2),d(1..2)),dp;
def S=Weyl();
setring S;  S;
==> // coefficients: QQ
==> // number of vars : 4
==> //        block   1 : ordering dp
==> //                  : names    x(1) x(2) d(1) d(2)
==> //        block   2 : ordering C
==> // noncommutative relations:
==> //    d(1)x(1)=x(1)*d(1)+1
==> //    d(2)x(2)=x(2)*d(2)+1
kill A1,S;
ring B1=0,(x1,d1,x2,d2),dp;
def S=Weyl(1);
setring S;  S;
==> // coefficients: QQ
==> // number of vars : 4
==> //        block   1 : ordering dp
==> //                  : names    x1 d1 x2 d2
==> //        block   2 : ordering C
==> // noncommutative relations:
==> //    d1x1=x1*d1+1
==> //    d2x2=x2*d2+1
See also: makeWeyl.