#6101: computation of induced morphism on homology and cohomology of simplicial
complex morphisms
-------------------------------------+-------------------------------------
Reporter: bantieau | Owner: bantieau
Type: enhancement | Status: needs_work
Priority: major | Milestone: sage-6.10
Component: algebraic | Resolution:
topology | Merged in:
Keywords: | Reviewers:
Authors: | Work issues:
Report Upstream: N/A | Commit:
Branch: u/jhpalmieri | ec81de20addced6a723f51413c3ffb31eaf4bc13
/induced-maps | Stopgaps:
Dependencies: #19179, #6102 |
-------------------------------------+-------------------------------------
Comment (by jhpalmieri):
Going this route tempts me to make `Simplex` inherit from `Element`, but
you might want to construct abstract instances of `Simplex` which are not
elements of any particular complex. So I can't use the `Element.__init__`
method, which requires setting a parent. As a result, I don't think I can
use `_element_constructor_` for simplicial complexes. Instead, I can do
something like this (plus doctests):
{{{
#!diff
diff --git a/src/sage/homology/simplicial_complex.py
b/src/sage/homology/simplicial_complex.py
index 8d00cd6..366c1db 100644
--- a/src/sage/homology/simplicial_complex.py
+++ b/src/sage/homology/simplicial_complex.py
@@ -1077,6 +1077,21 @@ class SimplicialComplex(Parent,
GenericCellComplex):
"""
return self._vertex_set
+ def _an_element_(self):
+ return self.facets()[0]
+
+ def __contains__(self, x):
+ if not isinstance(x, Simplex):
+ return False
+ dim = x.dimension()
+ return x in self.n_faces(dim)
+
+ def __call__(self, simplex): # not _element_constructor_
+ if simplex not in self:
+ raise ValueError
+ return simplex
+
def maximal_faces(self):
"""
The maximal faces (a.k.a. facets) of this simplicial complex.
}}}
Then the full test suite passes.
--
Ticket URL: <http://trac.sagemath.org/ticket/6101#comment:32>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
