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4.23.3 quickConeViaNormals

Syntax:
quickConeViaNormals( intmat IE )
quickConeViaNormals( intmat IE, intmat E )
quickConeViaNormals( intmat IE, intmat E, int flags )
Type:
cone
Purpose:
cone consisting of all points x, such that IE*x >= 0 in each component and (if stated) E*x = 0; inequalities and (if stated) equations will be not be transformed, only getting rid of obvious redundancies; flags may range between 0,..,3 defining an upper and lower bit (0=0*2+0, 1=0*2+1, 2=1*2+0, 3=1*2+1), if higher bit is 1, then program assumes each inequality yields a facet, if lower bit is 1, then program assumes the kernel of E is the span of the cone, if either bit is 0, then program computes the information itself.
Example:
 
intmat M[11][3]=
0,-1,1,
-1,1,0,
-1,0,1,
-1,-1,2,
-2,2,0,
-2,1,1,
-2,0,2,
-2,-1,3,
-3,2,1,
-3,1,2,
-3,0,3;
cone c=quickConeViaNormals(M);
c;
==> AMBIENT_DIM
==> 3
==> INEQUALITIES
==> -3,1,2,
==> -3,2,1,
==> -2,-1,3,
==> -2,1,1,
==> -1,-1,2,
==> -1,0,1,
==> -1,1,0,
==> 0,-1,1
==> EQUATIONS
==> 
cone d=coneViaNormals(M);
d;
==> AMBIENT_DIM
==> 3
==> INEQUALITIES
==> -1,1,0,
==> 0,-1,1
==> EQUATIONS
==> 

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