[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
## RE: [Axiom-developer] Axiom Design Question / Polymake feedback

**From**: |
Page, Bill |

**Subject**: |
RE: [Axiom-developer] Axiom Design Question / Polymake feedback |

**Date**: |
Wed, 24 Aug 2005 10:29:03 -0400 |

Martin,
On Wednesday, August 24, 2005 8:49 AM you wrote:
>* ... *
>* Now the problem is as follows: the type of the elements of the*
>* matrix depends on the polytope. For some polytopes, they are*
>* Integers, for others rationals or floats, or both.*
Ideally, I think you might want to return something like:
vertices: % -> Matrix Union (Integer, Float, Fraction Integer)
but unfortunately Axiom does not understand that domain
Union (Integer, Float, Fraction Integer) is actually a RING so
you are not allowed to call it a Matrix.
Instead you might use, for example:
vertices: % -> List List Union (Integer, Float, Fraction Integer)
or maybe
vertices: % -> TwoDimensionalArray Union (Integer, Float, Fraction
Integer)
but note that for some reason
(11) -> x: TwoDimensionalArray Union (Integer, Float, Fraction Integer)
:=new(2,2,0)
(1) [0,0,0,0]
Type: TwoDimensionalArray Union(Integer,Float,Fraction
Integer)
does not print properly (as an rectangular array).
I think there are two possible bug reports here:
1) Union ( list of alternatives that are coercible to some ring )
should be a RING
2) display of TwoDimensionalArray of type Union(...) is not properly
formatted
Do you agree?
Regards,
Bill Page.