ASKSAGE: Sage Q&A Forum - Latest question feedhttp://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Tue, 10 Mar 2015 01:13:07 -0500checking isomorphism for weighted bipartite graphhttp://ask.sagemath.org/question/26130/checking-isomorphism-for-weighted-bipartite-graph/Hi, guys,
I am working on a problem involving checking if two weighted bipartite graphs are isomorphic.
I saw I can define a weighted graph in sage like this:
sage: X = Matrix([(0,0,1,1),(0,0,1,2),(0,1,1,0)])
sage: XX = BipartiteGraph(X,weighted=True)
sage: Y = Matrix([(1,0,2,0),(1,0,0,1),(1,0,1,0)])
sage: YY = BipartiteGraph(Y,weighted=True)
sage: W = Matrix([(1,0,2,0),(1,0,0,1),(1,0,2,0)])
sage: WW = BipartiteGraph(Z,weighted=True)
I swapped rows and columns of matrix defining X to get Y, so Y is isomorphic to X,
But since my graphs are weighted, I changed one element in Y from 1 to 2 to get W,
yet it still tell me XX and WW are isomorphic
sage: YY.is_isomorphic(XX)
True
sage: ZZ.is_isomorphic(XX)
True
Are there other functions I can use to check isomorphism for weighted bipartite graph?skylibraryTue, 10 Mar 2015 01:13:07 -0500http://ask.sagemath.org/question/26130/Distinct (nonisomorphic) treeshttp://ask.sagemath.org/question/9993/distinct-nonisomorphic-trees/"Construct all non-isomorphic trees of order 7"
How to do that in Sage ?!
Please helpMohabSun, 07 Apr 2013 07:24:14 -0500http://ask.sagemath.org/question/9993/Does sage have analog of magma function IsIsomorphic?http://ask.sagemath.org/question/9651/does-sage-have-analog-of-magma-function-isisomorphic/Does Sage have analog of magma function [IsIsomorphic for curves](http://magma.maths.usyd.edu.au/magma/handbook/text/1253#13614)
> IsIsomorphic(C, D) : Crv, Crv -> BoolElt,MapSch
> Given irreducible curves C and D this
> function returns true is C and D are
> isomorphic over their common base
> field. If so, it also returns a scheme
> map giving an isomorphism between
> them. The curves C and D must be
> reduced. Currently the function
> requires that the curves are not both
> genus 0 nor both genus 1 unless the
> base field is finite.
or [IsIsomorphic for hyperelliptic curves](http://magma.maths.usyd.edu.au/magma/handbook/text/1391#15274)?
> IsIsomorphic(C1, C2) : CrvHyp, CrvHyp
> -> BoolElt, MapIsoSch
>
> SetVerbose("CrvHypIso", n): Maximum: 3
>
> This function returns true if and only if the hyperelliptic curves C1
> and C2 are isomorphic over their
> common base field. If the curves are
> isomorphic, an isomorphism is
> returned.petRUShkaWed, 26 Dec 2012 00:56:53 -0600http://ask.sagemath.org/question/9651/