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D.15.33.4 modJanet

Procedure from library rstandard.lib (see rstandard_lib).

Usage:
modJanet(I,i); I is an ideal, i an integer (optional).

Return:
ideal, a Janet basis for I using modular methods.

Purpose:
Computes a Janet basis for the ideal given by the generators in I using modular techniques.
If second argument is 0 then the result is not verified.

Example:
 
LIB "rstandard.lib";
ring R=0,(t,x,y,z),ds;
ideal i=
5t3x2z+2t2y3x5,
7y+4x2y+y2x+2zt,
3tz+3yz2+2yz4;
ideal j=modJanet(i);  j;
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> Length of Janet basis: 3
==> j[1]=y
==> j[2]=tz
==> j[3]=ty
ring S=0,(x,y,z),dp;
poly p1 =x2y*(47x5y7z3+28xy5z8+63+91x5y3z7);
poly p2 =xyz*(57y6+21x2yz9+51y2z2+15x2z4);
poly p3 =xy4z*(74y+32x6z7+53x5y2z+17x2y3z);
poly p4 =y3z*(21x2z6+32x10y6z5+23x5y5z7+27y2);
poly p5 =xz*(36y2z2+81x9y10+19x2y5z4+79x4z6);
ideal i =p1,p2,p3,p4,p5;
ideal j=modJanet(i,0);  j;
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> Length of Janet basis: 9
==> j[1]=x2y
==> j[2]=x3y
==> j[3]=x4y
==> j[4]=y5z
==> j[5]=x5y
==> j[6]=xy3z3
==> j[7]=xy5z
==> j[8]=xy4z3
==> j[9]=x5z7+36/79xy2z3
See also: rJanet.