Re: [sage-combinat-devel] Plotting permutations
Hi Nathann,
I am writing a patch for the recognition of Permutation graphs (and
comparability graphs, actually), and I thought that it would be nice
to have some way to plot the permutations built this way. Given a
permutation p on 1...n, you get the permutation graph by linking
together two vertices ij such that ij and p(i) p(j). Hence the kind
of plot I have in mind is the one you can see on the top-right corner
of his page :
http://en.wikipedia.org/wiki/Permutation_graph
I intended to write it, but there are two questions that need an
answer before doing that
1) Is it aready implemented in Sage somewhere ? I did not see it, but well :-)
The set {(i,j) | ij and p(i) p(j)} is called the set of the inversion of p
and is in Sage. Rather than the Graph, we use the matrix associated to it
under the name Rothe diagram or inversion diagram. We had it in MuPAD-Combinat
but it wasn't ported to Sage. See eg
http://www.mathe2.uni-bayreuth.de/frib/KERBER/h00/node29.html
It is closely related to the Lehmer code of the permutation which is in sage.
2) Is it useful to add it as a method of Permutation ? That is, should
it be implemented there or rather as a part of my recognition
algorithm, if it is only of interest for graph theoreticians ?
The algorithm I used to teach my Master students works as follows: Build an
orientation of the complete graph K_n as follows: for ij the arrow is
oriented
* j - i if (i,j) is an inversion (ie is in your Graph)
* i - j else
Then the inversion set (or the candidate permutation graph) comes from a
permutation if the resulting orientation of K_n is acyclic. Is it what you
want to implement (or maybe an optimization of it) ?
Now, to answer your question, I certainly would vote +1 on having a
Permutation.from_inversions methods which raise an error if the parameter is
not a proper inversion set. Alternatively, is_inversion_set returning True
or False is good too.
Cheers,
Florent
Thanks ! :-)
Nathann
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---
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and those who cannot.
---
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[sage-combinat-devel] Generating many classes, some of them with additional methods
Helloo Everybody !! The subject is not very clear, but given a few more lines I can make it a bit more explicit. Here is my problem : When #11880 we will have in Sage a database of graph classes. That is objects representing things like Interval Graphs, Planar Graphs, things like that. This database contains a HUGE number of classes (around 1000), and some of these graph classes are more famous than others. In particular, we have in Sage algorithms to tests whether a graph is planar, or an interval graph. Hence it would be nice to be able to use these methods like that : g in graph_classes.PlanarGraphs g in graph_classes.IntervalGraph To do so, the recognition methods should be reached by the __in__ method of each of those graph classes. And here is where the problem lies : I have on one hand a way to build Sage objects representing graph classes, and on the other hand recognition algorithms for SOME of them. How should I make the link between the two ? 1) Should any object representing a Graph class have a __in__ method which checks whether the class represented by the object has a recognition algorithm listed in a dictionnary somewhere ? 2) Should the graph classes objects be generated in such a way (how ?) such that its __in__ method is automatically the good one ? I expect you already had to deal with problems like that in your code, so just in case you already found a great answer to that. ;-) Thank yo !!! Nathann -- You received this message because you are subscribed to the Google Groups sage-combinat-devel group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
Re: [sage-combinat-devel] Plotting permutations
Hell !! I vote yes. When I teach this, I call this the swapping diagram (not standard terminology). The number of swaps gives you the Bruhat length, if I remember correctly, when you regard S_n as a Coxeter group. The parity gives you the sign of the permutation, which gives you, in turn, the determinant of the associated matrix. It is a very useful diagram:-) Hmmm I just took a look at it, and it seems I just can not do this for my own purposes. I mean, this diagram can be written, but Permutations objets basically *cannot* store a permutation between anything different from 1 n Well, it just supposes that the elements in the permutation have some natural linear ordering, which is the one given by the '' python operator. Here is the code from Permutation.inversions : p = self[:] inversion_list = [] for i in range(len(p)): for j in range(i+1,len(p)): if p[i] p[j]: #inversion_list.append((p[i],p[j])) inversion_list.append([i,j]) return inversion_list So it looks like I cannot trust it with my strings, for instance :-/ I will write this diagram anyway. It can prove useful to me later, and it looks like you could use it anyway ^^; It will be ticket #12872. Nathann -- You received this message because you are subscribed to the Google Groups sage-combinat-devel group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
[sage-combinat-devel] Drawings for Permutations -- how would you plot them ?
Helloo everybody !!! Because of a former post on this google group [1] I created the following patch [2]. It adds to Permutation objects a .show() method that produces this kind of drawings [3]. Hence, that would be the default way to plot Permutations in Sage. The thing is that it is the natural drawing for what I am current working on (Permutation graphs [4]), and David says he uses them and calls them Swapping diagrams -- which is non-standard according to him. Well. Do you think there should be other ways to draw permutations in Sage ? Do you have anything against that patch, which somehow makes these drawings the default ones ? If you like other type of drawings, I think it would be nice to have many arguments to the .show() method that would yield different kind of drawings, but the .show() method is definitely what I would look for if I were to try to plot a drawing, so I think that these drawings should be reachable through the .show() method, even if they are not the default ones. Well, I'm all ears now ! Give me your thoughts, mysterious sage-combinat crowd O_O Nathann [1] https://groups.google.com/d/topic/sage-combinat-devel/vdfE7iaJTxs/discussion [2] http://trac.sagemath.org/sage_trac/ticket/12872 [3] http://trac.sagemath.org/sage_trac/attachment/ticket/12872/tmp_1.png [4] http://en.wikipedia.org/wiki/Permutation_graph -- You received this message because you are subscribed to the Google Groups sage-combinat-devel group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
Re: [sage-combinat-devel] Drawings for Permutations -- how would you plot them ?
I typically draw them top-to-bottom. I've seen them called string diagrams by people in pattern avoidance. On Tue, Apr 24, 2012 at 8:24 AM, Nathann Cohen nathann.co...@gmail.com wrote: Helloo everybody !!! Because of a former post on this google group [1] I created the following patch [2]. It adds to Permutation objects a .show() method that produces this kind of drawings [3]. Hence, that would be the default way to plot Permutations in Sage. The thing is that it is the natural drawing for what I am current working on (Permutation graphs [4]), and David says he uses them and calls them Swapping diagrams -- which is non-standard according to him. Well. Do you think there should be other ways to draw permutations in Sage ? Do you have anything against that patch, which somehow makes these drawings the default ones ? If you like other type of drawings, I think it would be nice to have many arguments to the .show() method that would yield different kind of drawings, but the .show() method is definitely what I would look for if I were to try to plot a drawing, so I think that these drawings should be reachable through the .show() method, even if they are not the default ones. Well, I'm all ears now ! Give me your thoughts, mysterious sage-combinat crowd O_O Nathann [1] https://groups.google.com/d/topic/sage-combinat-devel/vdfE7iaJTxs/discussion [2] http://trac.sagemath.org/sage_trac/ticket/12872 [3] http://trac.sagemath.org/sage_trac/attachment/ticket/12872/tmp_1.png [4] http://en.wikipedia.org/wiki/Permutation_graph -- You received this message because you are subscribed to the Google Groups sage-combinat-devel group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en. -- You received this message because you are subscribed to the Google Groups sage-combinat-devel group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
Re: [sage-combinat-devel] Re: Do we want a metaclass framework?
On Mon, Apr 23, 2012 at 05:48:10AM -0700, Simon King wrote: ... Our current metaclasses all work by overriding a magical method of type, or adding a magical method to type. Ideally, this should be in a customisable way. In some cases, we want to override not just one method. Currently, each combination of customised methods requires to write a new metaclass. But why not have just *one* metametaclass CustomisationMetaclass, such that CustomisationMetaclass(init,get,reduce) returns a metaclass that allows customisation of three methods? An alternative would be to have a single metaclass, subclass of type, that adds hooks to enable at once all special methods for classes. Pros: - It's simple - It pushes toward eventually having all those hooks directly in type - It is similar to what happens for objects: all hooks are directly available; you just implement those that you need. Inconvenient: - If a class does not use a hook, does it still pay an overhead for the handling of this hook? For most hooks, that's irrelevant: if a class does not use the __classmul__ hook it won't use the syntax A*B either. But a couple of hooks like __classcall__, __classinit__ could slow basic usage. Cheers, Nicolas -- Nicolas M. Thiéry Isil nthi...@users.sf.net http://Nicolas.Thiery.name/ -- You received this message because you are subscribed to the Google Groups sage-combinat-devel group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
Re: [sage-combinat-devel] Re: Do we want a metaclass framework?
On Mon, Apr 23, 2012 at 05:59:04AM -0700, Simon King wrote: In CustomisationMetaclass, it should not be needed to explicitly state which methods are to be customised. Instead, CustomisationMetaclass should look if it finds a method named __classbla__ and would *automatically* customize type.__bla__. Hence, class MyClass(Parent): __metaclass__ = CustomisationMetaclass @staticmethod def __classadd__(... should suffice. I like this variant because it encapsulates the technical metaclass details. So we can easily change the implementation later on if we change our mind or find a better approach. Cheers, Nicolas -- Nicolas M. Thiéry Isil nthi...@users.sf.net http://Nicolas.Thiery.name/ -- You received this message because you are subscribed to the Google Groups sage-combinat-devel group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
[sage-combinat-devel] Re: Do we want a metaclass framework?
Hi Nicolas! On 2012-04-24, Nicolas M. Thiery nicolas.thi...@u-psud.fr wrote: On Mon, Apr 23, 2012 at 05:59:04AM -0700, Simon King wrote: Hence, class MyClass(Parent): __metaclass__ = CustomisationMetaclass @staticmethod def __classadd__(... should suffice. I like this variant because it encapsulates the technical metaclass details. So we can easily change the implementation later on if we change our mind or find a better approach. OK. But I think priority should be given to cythonization of the existing metaclasses. Namely, Florent found out how one can produce a cdef'd metaclasses, so that its instances (thus, usual classes) inherit the fast methods (like __call__). One can cdefine NestedClassMetaclass and derive from it a cdefined ClasscallMetaclass (my patch isn't posted yet). Together with some tricks that Florent presented in his original patch at #12808, one should get a considerable speedup in creation of classes. Also I found that one can simply rename sage/structure/dynamic_class.py into sage/structure/dynamic_class.pyx -- that alone should yield some speedup. And then one can likely gain even more from using Cython more properly. But independent of that, I think at some point I will try to produce a cdefined CustomisationMetaclass. *IF* it turns out that it can compete speed-wise, then we can still decide whether we should use it to refactor the existing metaclasses. Best regards, Simon -- You received this message because you are subscribed to the Google Groups sage-combinat-devel group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
Re: [sage-combinat-devel] Re: Do we want a metaclass framework?
On Tue, Apr 24, 2012 at 07:23:27PM +, Simon King wrote: OK. But I think priority should be given to cythonization of the existing metaclasses. Namely, Florent found out how one can produce a cdef'd metaclasses, so that its instances (thus, usual classes) inherit the fast methods (like __call__). One can cdefine NestedClassMetaclass and derive from it a cdefined ClasscallMetaclass (my patch isn't posted yet). Together with some tricks that Florent presented in his original patch at #12808, one should get a considerable speedup in creation of classes. +1 Also I found that one can simply rename sage/structure/dynamic_class.py into sage/structure/dynamic_class.pyx -- that alone should yield some speedup. And then one can likely gain even more from using Cython more properly. Yes, I have seen that (but see my comment on the ticket) But independent of that, I think at some point I will try to produce a cdefined CustomisationMetaclass. *IF* it turns out that it can compete speed-wise, then we can still decide whether we should use it to refactor the existing metaclasses. +1 Cheers, Nicolas -- Nicolas M. Thiéry Isil nthi...@users.sf.net http://Nicolas.Thiery.name/ -- You received this message because you are subscribed to the Google Groups sage-combinat-devel group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
Re: [sage-combinat-devel] Plotting permutations
On Tue, Apr 24, 2012 at 12:51:34PM +0200, Nathann Cohen wrote: Hell !! I vote yes. When I teach this, I call this the swapping diagram (not standard terminology). The number of swaps gives you the Bruhat length, if I remember correctly, when you regard S_n as a Coxeter group. The parity gives you the sign of the permutation, which gives you, in turn, the determinant of the associated matrix. It is a very useful diagram:-) Hmmm I just took a look at it, and it seems I just can not do this for my own purposes. I mean, this diagram can be written, but Permutations objets basically *cannot* store a permutation between anything different from 1 n Well, it just supposes that the elements in the permutation have some natural linear ordering, which is the one given by the '' python operator. Here is the code from Permutation.inversions : p = self[:] inversion_list = [] for i in range(len(p)): for j in range(i+1,len(p)): if p[i] p[j]: #inversion_list.append((p[i],p[j])) inversion_list.append([i,j]) return inversion_list So it looks like I cannot trust it with my strings, for instance :-/ I will write this diagram anyway. It can prove useful to me later, and it looks like you could use it anyway ^^; You might want to use permutations from the symmetric group instead:: sage: S = SymmetricGroup(10) sage: x = S.random_element() sage: x.inversions() [(2,3), (2,4), (2,5), (4,5), (3,5), (1,5), (2,6), (4,6), (3,6), (1,6), (5,6), (2,7), (4,7), (3,7), (1,7), (2,8), (4,8)] It has been implemented recently by Mark, and it will work for any Coxeter group. Cheers, Nicolas -- Nicolas M. Thiéry Isil nthi...@users.sf.net http://Nicolas.Thiery.name/ -- You received this message because you are subscribed to the Google Groups sage-combinat-devel group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
Re: [sage-devel] sagenb.org is unusably slow
On 2012-04-24 05:49, Dima Pasechnik wrote: On Monday, 23 April 2012 21:02:05 UTC+8, William wrote: On Mon, Apr 23, 2012 at 12:11 AM, Dan Drake wrote: sagenb.org http://sagenb.org is so slow as to be unusable right now. Can someone investigate? Perhaps restart it? It gets automatically restarted twice a day anyways. It's just massively overused compared to the server resources and scalability of the app.Encourage me to do a complete truly scalable rewrite on scalable infrastructure... Would one still need hardware and bandwidth way beyond what NSF and other grants can pay for, if the usage growth continues like this? Isn't the main bottleneck software currently? -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
[sage-devel] Artithmetics in p-adic extensions?
Is there any progress in making SAGE support artithmetics in (ramified) p-adic extensions? -Karl -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
[sage-devel] Re: inferior sage in emacs, bug?
I confirm I getting the same bug, in emacs 24, sage 5, getting Wrong type argument: hash-table-p, nil buffer *SAGE-main* is in commint-run mode. No inferior-sage-mode. I have to run inferior-sage-mode, manually. I have installed sage-mode-0.6 and sage-mode-0.7 directly from sage website I also checked Ivan's sage_mode-0.8. The error is persistant in all version. בתאריך יום שלישי, 10 באפריל 2012 15:38:54 UTC-6, מאת Ezequiel Birman: Are sage-mode inferior-sage-mode and sage-view still supported? I (kind of) managed to get an Inferior Sage. Is there a way to eval last expresion in sage-mode instead of the whole buffer (C-c C-r)? I am using latest sage (4.8) and sage-mode cloned from mercurial repo. (by the way, I've built and installed sage-mode python packages in the default location: /usr/lib/python2.7/site-packages/ Should I move them under the sage dir hierarchy? ie. overwrite the old python packages installed by sage 4.8?) After 'M-x sage' i got this error: compilation-forget-errors: Wrong type argument: hash-table-p, nil and buffer *SAGE-main* is in commint-run mode. No inferior-sage-mode. The problem seems to lie in python-send-command. I'm not quite sure, but i've added ;;; hack to avoid error in python-send-command (add-hook 'sage-startup-before-prompt-hook (lambda () (compilation-minor-mode 1))) which initializes a hash table needed by compilation-mode, to my .emacs. Now, after 'M-x sage' *SAGE-main* pops-up properly but i still get: comint-redirect-send-command-to-process: No prompt found or `comint-prompt-regexp' not set properly but comint-prompt-regexp local value for buffer *SAGE-main* is: ^\\(?:\\(?:\\(?:(\\(?:[Pg]db)\\)\\|\\.\\.\\.\\(?:\\.\\.\\)?\\|\\|ipdb\\|sage:\\)\\) \\)+ Here is a portion of my .emacs: sage-mode ;;; https://bitbucket.org/ncalexan/sage-mode ;;; http://wiki.sagemath.org/sage-mode ;;(add-to-list 'load-path /usr/local/share/sage/data/emacs) (add-to-list 'load-path /usr/local/src/sage/sage-mode/emacs) (require 'sage) (setq sage-command /usr/local/share/sage/sage) ;; If you want sage-view to typeset all your output and have plot() ;; commands inline, uncomment the following line and configure sage-view: (autoload 'sage-view sage-view t) ;; (add-hook 'sage-startup-before-prompt-hook ;; (lambda () ;; (set (make-local-variable 'compilation-locs) ;; (make-hash-table :test 'equal :weakness 'value ;; (remove-hook 'sage-startup-before-prompt-hook 'sage-send-startup-before-prompt-command) (add-hook 'inferior-sage-mode-hook (function (lambda () ;;(setq comint-redirect-perform-sanity-check t) (sage-view) ;; (sage-view-enable-inline-output) ;; (sage-view-enable-inline-plots) ))) ;;; hack to avoid error in python-send-command (add-hook 'sage-startup-before-prompt-hook (lambda () (compilation-minor-mode 1))) (add-hook 'sage-mode-hook '(lambda () ; taken from http://www.cs.caltech.edu/courses/cs11/material/python/misc/python_style_guide.html#TABS (set-variable 'py-indent-offset 4) (set-variable 'py-smart-indentation nil) (set-variable 'indent-tabs-mode nil))) Thank you -- Ezequiel Birman -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
Re: [sage-devel] sagenb.org is unusably slow
On Tuesday, 24 April 2012 15:59:22 UTC+8, Jeroen Demeyer wrote: On 2012-04-24 05:49, Dima Pasechnik wrote: On Monday, 23 April 2012 21:02:05 UTC+8, William wrote: On Mon, Apr 23, 2012 at 12:11 AM, Dan Drake wrote: sagenb.org http://sagenb.org is so slow as to be unusable right now. Can someone investigate? Perhaps restart it? It gets automatically restarted twice a day anyways. It's just massively overused compared to the server resources and scalability of the app.Encourage me to do a complete truly scalable rewrite on scalable infrastructure... Would one still need hardware and bandwidth way beyond what NSF and other grants can pay for, if the usage growth continues like this? Isn't the main bottleneck software currently? If 1% of registered sagenb users would run stuff on boxen at the same time, this would be 900 instances of sagenb. I doubt boxen can handle this smoothly, even if they were interactive non-graphic terminal sessions. -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
[sage-devel] Mathematica language vs. python
Here is a very interesting informal survey of Mathematica qualities. It looks like people are asked to rate different languages against different statements: http://hammerprinciple.com/therighttool/items/mathematica Notice that the ratings are most dissimilar from Python (see bottom of page)! Indeed, it is very interesting to look at the comparison page: http://hammerprinciple.com/therighttool/items/mathematica/python Thanks, Jason -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
[sage-devel] Re: ARM port (again)
There is no /dev/shm in my android system. Could it be that this is the problem? If so, is there any hope of solving it? -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
[sage-devel] Re: ARM port (again)
Nevermind, it worked by mounting an empty tmpfs as shm device On 24 abr, 18:07, mmarco mma...@unizar.es wrote: There is no /dev/shm in my android system. Could it be that this is the problem? If so, is there any hope of solving it? -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
[sage-devel] Re: Mathematica language vs. python
Jason Grout jason-s...@creativetrax.com writes: Notice that the ratings are most dissimilar from Python (see bottom of page)! Indeed, it is very interesting to look at the comparison page: http://hammerprinciple.com/therighttool/items/mathematica/python I find it a little bizarre that almost 40% of respondents consider Python better at symbolic manipulation than Mathematica. Mathematica is practically built for symbolic manipulation, and in Sage a lot of hard work has gone into pynac because plain Python does not have symbolics support. Why does Mathematica supposedly have a strong static type system? It's an interpreted language... Also interesting is that Mathematica beats Python at numeric computing (62%), but Python strikes back with a victory in scientific computing (81%)... huh? Certainly an interesting listing, though maybe one should not set too much stock by it since there are only a couple dozen respondents as yet. -Keshav Join us in #sagemath on irc.freenode.net ! -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
Re: [sage-devel] Artithmetics in p-adic extensions?
Sage currently supports arithmetic in totally ramified p-adic extensions defined by an Eisenstein polynomial. There is progress in more general extensions in the last few months, but I've been really busy with other projects as well. What kind of extensions do you need? David On Tue, Apr 24, 2012 at 07:02, Karl jk.lind...@gmail.com wrote: Is there any progress in making SAGE support artithmetics in (ramified) p-adic extensions? -Karl -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
[sage-devel] Re: inferior sage in emacs, bug?
sage-update-autoloads also did not solve my problem, but with the hack of Ezequiel ;;; hack to avoid error in python-send-command (add-hook 'sage-startup-before-prompt- hook (lambda () (compilation-minor-mode 1))) it works fine. It could be emacs 24 thing. בתאריך יום שלישי, 24 באפריל 2012 08:27:29 UTC-6, מאת syd.la...@gmail.com: I confirm I getting the same bug, in emacs 24, sage 5, getting Wrong type argument: hash-table-p, nil buffer *SAGE-main* is in commint-run mode. No inferior-sage-mode. I have to run inferior-sage-mode, manually. I have installed sage-mode-0.6 and sage-mode-0.7 directly from sage website I also checked Ivan's sage_mode-0.8. The error is persistant in all version. בתאריך יום שלישי, 10 באפריל 2012 15:38:54 UTC-6, מאת Ezequiel Birman: Are sage-mode inferior-sage-mode and sage-view still supported? I (kind of) managed to get an Inferior Sage. Is there a way to eval last expresion in sage-mode instead of the whole buffer (C-c C-r)? I am using latest sage (4.8) and sage-mode cloned from mercurial repo. (by the way, I've built and installed sage-mode python packages in the default location: /usr/lib/python2.7/site-packages/ Should I move them under the sage dir hierarchy? ie. overwrite the old python packages installed by sage 4.8?) After 'M-x sage' i got this error: compilation-forget-errors: Wrong type argument: hash-table-p, nil and buffer *SAGE-main* is in commint-run mode. No inferior-sage-mode. The problem seems to lie in python-send-command. I'm not quite sure, but i've added ;;; hack to avoid error in python-send-command (add-hook 'sage-startup-before-prompt-hook (lambda () (compilation-minor-mode 1))) which initializes a hash table needed by compilation-mode, to my .emacs. Now, after 'M-x sage' *SAGE-main* pops-up properly but i still get: comint-redirect-send-command-to-process: No prompt found or `comint-prompt-regexp' not set properly but comint-prompt-regexp local value for buffer *SAGE-main* is: ^\\(?:\\(?:\\(?:(\\(?:[Pg]db)\\)\\|\\.\\.\\.\\(?:\\.\\.\\)?\\|\\|ipdb\\|sage:\\)\\) \\)+ Here is a portion of my .emacs: sage-mode ;;; https://bitbucket.org/ncalexan/sage-mode ;;; http://wiki.sagemath.org/sage-mode ;;(add-to-list 'load-path /usr/local/share/sage/data/emacs) (add-to-list 'load-path /usr/local/src/sage/sage-mode/emacs) (require 'sage) (setq sage-command /usr/local/share/sage/sage) ;; If you want sage-view to typeset all your output and have plot() ;; commands inline, uncomment the following line and configure sage-view: (autoload 'sage-view sage-view t) ;; (add-hook 'sage-startup-before-prompt-hook ;; (lambda () ;; (set (make-local-variable 'compilation-locs) ;; (make-hash-table :test 'equal :weakness 'value ;; (remove-hook 'sage-startup-before-prompt-hook 'sage-send-startup-before-prompt-command) (add-hook 'inferior-sage-mode-hook (function (lambda () ;;(setq comint-redirect-perform-sanity-check t) (sage-view) ;; (sage-view-enable-inline-output) ;; (sage-view-enable-inline-plots) ))) ;;; hack to avoid error in python-send-command (add-hook 'sage-startup-before-prompt-hook (lambda () (compilation-minor-mode 1))) (add-hook 'sage-mode-hook '(lambda () ; taken from http://www.cs.caltech.edu/courses/cs11/material/python/misc/python_style_guide.html#TABS (set-variable 'py-indent-offset 4) (set-variable 'py-smart-indentation nil) (set-variable 'indent-tabs-mode nil))) Thank you -- Ezequiel Birman -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
Re: [sage-devel] Re: ARM port (again)
Em 24 de abril de 2012 13:46, mmarco mma...@unizar.es escreveu: Nevermind, it worked by mounting an empty tmpfs as shm device Good to know the real issue :-) My workaround only works for missing /dev/shm. Missing /dev/pts on build chroots I managed to bug at Mandriva sometime ago, to get it properly mounted in build nodes, otherwise it cannot generate documentation because gap would fail to start. On 24 abr, 18:07, mmarco mma...@unizar.es wrote: There is no /dev/shm in my android system. Could it be that this is the problem? If so, is there any hope of solving it? Paulo -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
[sage-devel] Re: Mathematica language vs. python
Someone should tell the survey people that it's is not the possessive form of it. It's is a contraction for it is. The possessive is its. If you want a slightly more informative comparison, try common lisp vs python. Crowdsourcing on opinions of programming languages seems like a pretty poor way of garnering information other than uncalibrated, uh, opinions. -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
Re: [sage-devel] Re: Mathematica language vs. python
On 04/24/12 06:21 PM, Keshav Kini wrote: Jason Groutjason-s...@creativetrax.com writes: Notice that the ratings are most dissimilar from Python (see bottom of page)! Indeed, it is very interesting to look at the comparison page: http://hammerprinciple.com/therighttool/items/mathematica/python I find it a little bizarre that almost 40% of respondents consider Python better at symbolic manipulation than Mathematica. Mathematica is practically built for symbolic manipulation, and in Sage a lot of hard work has gone into pynac because plain Python does not have symbolics support. snip -Keshav Join us in #sagemath on irc.freenode.net ! There appear to be numerous strange results on that site, so I take the results with a pinch of salt. I decided to compare MATLAB and Mathematica. http://hammerprinciple.com/therighttool/items/mathematica/matlab 1) I use this language out of choice 7 out of 8 picked Mathematica over Matlab Now it is pretty clear to me that there are FAR more people programming in MATLAB than Mathematica, and a lot of people like MATLAB. (Do a search on a job site and see how many jobs want Mathematica programmers vs MATLAB ones). So why 87% program in Mathematica out of choice is strange to me. 2) When I run into problems my colleagues can provide me with immediate help with this language 7 out of 9 picked Matlab over Mathematica. Funny that result, given the result to (1). 7 out of 8 chose Mathematica over MATLAB out of choice, but 7 out of 9 find their colleagues can help them with MATLAB more than Mathematica. 3) When I write code in this language I can be very sure it is correct 7 out of 8 picked Mathematica over Matlab Come on, which a stupid question. How the can you be much more sure Mathematica code is more correct than MATLAB code? The site looks good for a laugh, but does not appear to have any value other than that to me. Dave -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
Re: [sage-devel] Re: Mathematica language vs. python
On 04/24/12 06:21 PM, Keshav Kini wrote: I find it a little bizarre that almost 40% of respondents consider Python better at symbolic manipulation than Mathematica.Mathematica is practically built for symbolic manipulation, and in Sage a lot of hard work has gone into pynac because plain Python does not have symbolics support. Yes, could not agree more. -Keshav A bizarre result. Clearly Mathematica is better at symbolics. Arguably it is the best language for this. Perhaps it's skewed by the fact considerably more people use Python than Mathematica. If 1000x as many people use Python than do Mathematica, than you might expect more people to find Python good for symbolics than you do Mathematica. The results seem odd all around. The rest of it should go to /dev/null! Dave -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
