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Polyhedra :: rays(PolyhedralObject)

rays(PolyhedralObject) -- displays all rays of a Cone, a Fan, or a Polyhedron

Synopsis

Description

rays returns the rays of the input as the columns of the matrix R.

Please see V- and H-representation on the conventions we use for cones and polyhedra.

i1 : P = convexHull(matrix {{1,-1,2,-2},{1,1,2,2}}, matrix {{0},{1}})

o1 = P

o1 : Polyhedron
i2 : rays P

o2 = | 0 |
     | 1 |

              2        1
o2 : Matrix QQ  <--- QQ
i3 : C = coneFromVData P

o3 = C

o3 : Cone
i4 : rays C

o4 = | -1 1 |
     | 1  1 |

              2        2
o4 : Matrix ZZ  <--- ZZ
i5 : F = normalFan P

o5 = F

o5 : Fan
i6 : rays F

o6 = | -1 1 0 -1 1 |
     | 0  0 1 1  1 |

              2        5
o6 : Matrix ZZ  <--- ZZ