[sage-support] direct product and direct sum of groups

How can I calculate the direct product of two groups and/or the direct sum? For example given: G.=FreeGroup() H=G.quotient([x*y]) how do I calculate H+H and HxH? -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group an

Re: [sage-support] Find group from matrix presentation

I think the author uses "present" to say "generate" Il giorno mercoledì 24 marzo 2021 alle 09:35:05 UTC+1 vdelecroix ha scritto: > What does it mean "it presents Z5"? > > Le 24/03/2021 à 09:28, Mattia Villani a écrit : > > That matrix comes from the

Re: [sage-support] Find group from matrix presentation

the group it generates > in GL(2,QQ) is necessarily infinite. > > Le 24/03/2021 à 08:47, Mattia Villani a écrit : > > I do not have real code, only a matrix: > > > > matrix([[1,-3],[-3,4]]) > > > > which should be a representation of the group Z5: I want to veri

Re: [sage-support] Find group from matrix presentation

I do not have real code, only a matrix: matrix([[1,-3],[-3,4]]) which should be a representation of the group Z5: I want to verify it with Sage Il giorno martedì 23 marzo 2021 alle 17:18:12 UTC+1 dim...@gmail.com ha scritto: > On Tue, Mar 23, 2021 at 2:00 PM Mattia Villani wrote: > &g

[sage-support] Find group from matrix presentation

Is is possible to find the group given the matrix presentation? -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To vie

[sage-support] How to cite?

I have used Sagemath for my work: are there any pubblications I can cite to acknowledge sagemath authors? -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-s

[sage-support] How to define a generic function?

I am trying to calculate the general expression of the Kretschmann scalar of metric depending a non specified function m(r): how do I define such a function? II have tried with def m(r) but it is wrong since it expects a definition of the function -- You received this message because you are

[sage-support] Re: Parallelization of contractions

the processors. Il giorno mercoledì 22 gennaio 2020 07:43:52 UTC+1, Mattia Villani ha scritto: > > How to use parallelization on contraction of tensor? Consider the case I > have two successive contraction like this: > > Tud=etuu['^{ab}']*eamup['^c_b'] >

[sage-support] Parallelization of contractions

How to use parallelization on contraction of tensor? Consider the case I have two successive contraction like this: Tud=etuu['^{ab}']*eamup['^c_b'] Tp=Tud['^{ab}']*eamup['^c_a'] How con I parallelize it? -- You received this message because you are subscribed to the Google Groups "sage-suppor

[sage-support] Memory efficient calculation of the Kretschmann scalar

Currently I use the following code to calculate the Kretschmann scalar kr of my metric g: R=g.Riemann(); uR=R.up(g) dR=R.down(g) kr=uR['^{abcd}']*dR['_{abcd}'] It works, but it consumes a lot of memory: is there a more memory efficient way to calculate the Kretschamann scalar? -- You receive

Re: [sage-support] Condition of type: STORAGE-EXHAUSTED

of the Kretschmann scalar from theta=pi") print(limit(limit(kr.expr().subs(m=10,L=1,A=6,alpha=2,beta=4),th=pi),r=0)) Il giorno venerdì 20 dicembre 2019 11:11:46 UTC+1, Jori Mäntysalo (TAU) ha scritto: > > On Thu, 19 Dec 2019, Mattia Villani wrote: > > >

[sage-support] Condition of type: STORAGE-EXHAUSTED

I got the error Condition of type: STORAGE-EXHAUSTED while running my program. After some Googling I have found that it means that my program has reached the memory limit. My question is: how to incr

[sage-support] How to increase the memory that SageMath can use?

While running my program (after a few hours of computation), Sage threw the error Condition of type: STORAGE-EXHAUSTED After some Googling i have found out that this is due to the fact that Sage ha