ASKSAGE: Sage Q&A Forum - RSS feedhttps://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Fri, 08 Dec 2017 16:25:22 +0100Running Error in my programhttps://ask.sagemath.org/question/39982/running-error-in-my-program/In my research I need to find some property of non_commuting graph of a special linear group SL(3,q)
sage: G=SL(3,4)
sage: G.order()
sage: E=G.list()
sage: Z=G.center()
sage: A=matrix(G.order())
sage: for i in range(G.order()):
for j in range(G.order()):
if E[i]*E[j]<>E[j]*E[i]:
A[i,j]=1
sage: graph=Graph(A
sage: for j in range(G.order()):
if E[i].matrix()==Z[j]:
graph.delete_vertex(i)
sage: I=graph.independent_set()
sage: len(I)
sage: cv=graph.vertexvover()
sage: len(cv)
sage: graph.clique_number()
sage: graph.chromatic_number`
but I have problem with large data size .
How can write these program to avoid the problem .Wed, 06 Dec 2017 22:57:37 +0100https://ask.sagemath.org/question/39982/running-error-in-my-program/Comment by dan_fulea for <p>In my research I need to find some property of non_commuting graph of a special linear group SL(3,q)</p>
<pre><code> sage: G=SL(3,4)
sage: G.order()
sage: E=G.list()
sage: Z=G.center()
sage: A=matrix(G.order())
sage: for i in range(G.order()):
for j in range(G.order()):
if E[i]*E[j]<>E[j]*E[i]:
A[i,j]=1
sage: graph=Graph(A
sage: for j in range(G.order()):
if E[i].matrix()==Z[j]:
graph.delete_vertex(i)
sage: I=graph.independent_set()
sage: len(I)
sage: cv=graph.vertexvover()
sage: len(cv)
sage: graph.clique_number()
sage: graph.chromatic_number`
</code></pre>
<p>but I have problem with large data size .
How can write these program to avoid the problem .</p>
https://ask.sagemath.org/question/39982/running-error-in-my-program/?comment=39993#post-id-39993The matrix $A$ above is huge,
sage: G = SL(3,4)
sage: G.order()
60480
sage: G.center().order()
3
it is a $60480\times 60480$ matrix. (And removing the center does not help too much.)
It is hard to store such a matrix. So the problem is not suited for a computer program.Thu, 07 Dec 2017 12:18:24 +0100https://ask.sagemath.org/question/39982/running-error-in-my-program/?comment=39993#post-id-39993Comment by Iguananaut for <p>In my research I need to find some property of non_commuting graph of a special linear group SL(3,q)</p>
<pre><code> sage: G=SL(3,4)
sage: G.order()
sage: E=G.list()
sage: Z=G.center()
sage: A=matrix(G.order())
sage: for i in range(G.order()):
for j in range(G.order()):
if E[i]*E[j]<>E[j]*E[i]:
A[i,j]=1
sage: graph=Graph(A
sage: for j in range(G.order()):
if E[i].matrix()==Z[j]:
graph.delete_vertex(i)
sage: I=graph.independent_set()
sage: len(I)
sage: cv=graph.vertexvover()
sage: len(cv)
sage: graph.clique_number()
sage: graph.chromatic_number`
</code></pre>
<p>but I have problem with large data size .
How can write these program to avoid the problem .</p>
https://ask.sagemath.org/question/39982/running-error-in-my-program/?comment=40014#post-id-40014I'm not sure you really mean "not suited for a computer program". It's just suited for a computer with a lot more memory.Fri, 08 Dec 2017 16:25:22 +0100https://ask.sagemath.org/question/39982/running-error-in-my-program/?comment=40014#post-id-40014