Cantor 17.12 crashes working with R and Sage backends and is very slow with some other ones on Arch Linux.

Fernando de Morais fernandodemorais.jf at
Sat Jan 13 18:49:17 UTC 2018

Hello Alexander,

I've been trying to recompile Cantor for enable the debug possibilities,
but I did not succeed. I run into a GPG error that I can't solve.

So I apologize for this failure of mine.

Currently I'm using maxima-ecl 5.41.0-1 and sagemath 8.1-4.

One more time I want to thank for quick relies and support.

2018-01-13 7:39 GMT-03:00 Alexander Semke <alexander.semke at>:

> Hello Fernando,
> thank you for your warm words about KDE and Cantor :-)
> The connection to and the initialization of a backend process takes some
> time. The times are different for different backends.
> Your observations about the long evaluation times for the first expression
> and almost instant evaluation of the subsequent expressions
> is because of the recent improvement that was done in 17.12. Previously,
> the initialization was done during the creation of a new session.
> So, when opening a project file the user had to wait until the
> initialization is done even in cases where he/she doesn't plan to modify
> the worksheet at all.
> This was changed. The creation of a new session or opening of saved
> project files is much faster now and the initialization of the backend
> process is
> postponed to the point when the user really asks Cantor to evaluate
> something.
> The recommended versions for R and Sage are missing, yes. But those are
> minor issues compared to the crashes you have. Let's have a look at them
> first.
> Which versions of Maxima and Sage are you using? Any chance to install the
> debuginfo package for Cantor and to try again? Without the debug symbols
> the crash dumps are not really useful...
> Connection to R is broken, the fix for this is "work in progress" at the
> moment.
> Regards,
> Alexander
> P.S.: @kde-edu moderators: no need to approve my previous email containing
> all the screenshots again.


*José Fernando de Morais Firmino.*
Graduando no Curso Superior de Tecnologia em Automação Industrial.
*IFPB,* Campus Cajazeiras.
Currículo Lattes: clique aqui <>.
Diretório de Grupos de Pesquisa: clique aqui
E-mail acadêmico: fernando.morais at
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