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Edit detail for SandBox polymake revision 2 of 2

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Time: 2007/11/18 18:31:44 GMT-8
Note: links updated after rename


        

Here we demonstrate the PolyMake wrappers Polytope and SimplicialComplex.

To use the Polytope domain we need to say

fricas
(1) -> )lib STRCNV READFILE POLYTOPE
StringConversions is now explicitly exposed in frame initial StringConversions will be automatically loaded when needed from /var/aw/var/LatexWiki/STRCNV.NRLIB/STRCNV ReadFile is now explicitly exposed in frame initial ReadFile will be automatically loaded when needed from /var/aw/var/LatexWiki/READFILE.NRLIB/READFILE Polytope is now explicitly exposed in frame initial Polytope will be automatically loaded when needed from /var/aw/var/LatexWiki/POLYTOPE.NRLIB/POLYTOPE

To create a cube of dimension 4 and look at its h-vector, we say

fricas
c5 := cube 5

\label{eq1}\verb#"cube5"#(1)
Type: Polytope
fricas
h5 := hVector c5
>> Error detected within library code: End of file

The idea is to factor the h-polynomial, for example:

fricas
factor reduce(+, [h5.(i+1) * t^i for i in 0..#h5-1])
There are 2 exposed and 2 unexposed library operations named # having 1 argument(s) but none was determined to be applicable. Use HyperDoc Browse, or issue )display op # to learn more about the available operations. Perhaps package-calling the operation or using coercions on the arguments will allow you to apply the operation.
Cannot find a definition or applicable library operation named # with argument type(s) Variable(h5)
Perhaps you should use "@" to indicate the required return type, or "$" to specify which version of the function you need.

Of course, the cube is simple:

fricas
simple c5
>> Error detected within library code: End of file

Here are its vertices:

fricas
vertices c5
>> Error detected within library code: End of file

Here is a random polytope with 6 vertices on the 3-dimensional sphere

fricas
r5 := randSphere(3, 6)

\label{eq2}\verb#"randsphere36"#(2)
Type: Polytope

Now vertices spits out a matrix containing the coordinates of the vertices of the polytope:

fricas
vertices r5
>> Error detected within library code: End of file