Equalities/Inequalities in Polyhedron()

assadabbasi
43 ●5 ●6 ●12

5311 ●4 ●44 ●118

Hi,

Anyone can please tell me that what equalities/inequalities in polyhedron(eqns = [()]) represent. e.g. for the following expression

P = Polyhedron(eqns=[(0,0,1,0)]) plane2.Hrepresentation()

The result is (An equation (0, 1, 0) x + 0 == 0,). Does it mean x2 = 0 plane in 3D?

Similarly for

plane3 = Polyhedron(eqns=[(1,0,0,-1)]) plane3.Hrepresentation()

the result is (An equation (0, 0, 1) x - 1 == 0,). Does it mean x3 = 1 in 3D.

If not so, how do we interpret it?

Thanks

1 Answer

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twch
368 ●3 ●13 ●21

Yes you are completely right

eqns=[(a,b,c,d)]

means exactly

a+b*x_1+c*x_2+d*x_3=0

The same is true for inequalities where = is replaced by ">=".

You can also plot the corresponding surface in R^3 with

plane3.show()

which should make clear who to interpret the equation.

Thanks for the clarification

assadabbasi ( 2013-02-19 18:06:26 +0100 )edit

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Asked: 2013-02-19 00:44:44 +0100

Seen: 448 times

Last updated: Feb 19 '13