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Volume of a Voronoi cell is wrong #37086

@seblabbe

Description

@seblabbe

Steps To Reproduce

sage: from sage.modules.free_module_integer import IntegerLattice
sage: l  = [7, 0, -1, -2, -1, -2, 7, -2, 0, 0, -2, 0, 7, -2, 0, -1, -2, -1, 7, 0 , -1, -1, 0, -2, 7]
sage: M = matrix(5, 5, l)
sage: c = IntegerLattice(M).voronoi_cell()

sage: M
[ 7  0 -1 -2 -1]
[-2  7 -2  0  0]
[-2  0  7 -2  0]
[-1 -2 -1  7  0]
[-1 -1  0 -2  7]
sage: c
A 5-dimensional polyhedron in QQ^5 defined as the convex hull of 598 vertices     

Expected Behavior

The volume of c should be equal to the determinant of M:

sage: c.volume()
12858
sage: M.det()
12858

Actual Behavior

sage: c.volume()
138219104/10715
sage: n(_)
12899.5897340177

Additional Information

This was first reported here:

https://ask.sagemath.org/question/74836/is-there-a-problem-in-voronoi-cell-computation/

Environment

- **OS**: Ubuntu 22.04.1 LTS
- SageMath version 10.2, Release Date: 2023-12-03
- Using Python 3.10.12. Type "help()" for help.

Checklist

  • I have searched the existing issues for a bug report that matches the one I want to file, without success.
  • I have read the documentation and troubleshoot guide

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