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D.13.1.17 dualCone

Procedure from library gfan.lib (see gfan_lib).

Usage:
dualCone(c); c cone

Return:
cone, the dual of c

Example:
 
LIB "gfan.lib";
intmat M1[2][2]=
1,0,
0,1;
cone c1=coneViaPoints(M1);
cone d1=dualCone(c1);
d1;
==> AMBIENT_DIM
==> 2
==> INEQUALITIES
==> 0,1,
==> 1,0
==> LINEAR_SPAN
==> 
==> 
print(rays(d1));
==> 1,0,
==> 0,1
intmat M2[2][2]=
1,1,
0,1;
cone c2=coneViaPoints(M2);
cone d2=dualCone(c2);
d2;
==> AMBIENT_DIM
==> 2
==> INEQUALITIES
==> 0,1,
==> 1,1
==> LINEAR_SPAN
==> 
==> 
print(rays(d2));
==>  1,0,
==> -1,1