[sage-support] Re: getting output of one matrix row in two workbook lines
> Use > > show(foo) > > to typeset an output line, which won't word wrap. This gives me latex output? > Or, after getting output as you do above, just click to the left of > the output to toggle through: > word wrap --> no word wrap --> hide This works! Thanks a lot. Mate --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Minimal notebook - just 1 cell
On Jan 19, 2009, at 11:42 PM, Timothy Clemans wrote: > > Is this similar to making it easy to post @interact demonstrations on > webpages including a blog? Well, there is a new Python blog engine being done by some of the same people who did Sphinx. http://zine.pocoo.org/ It would be nice if @interact demonstrations and cells (both read-only and read-write) could be added to blog entries. Cheers, Tim. --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Minimal notebook - just 1 cell
Is this similar to making it easy to post @interact demonstrations on webpages including a blog? On Mon, Jan 19, 2009 at 11:39 PM, William Stein wrote: > > On Mon, Jan 19, 2009 at 8:32 PM, Skylar wrote: >> >> Well, I am certainly no javascript master. I think maybe the best >> that I can do is to understand the simple server and build from there. >> >> Maybe I can do it in some number of months half-time. It would be a >> useful adaptation to introduce kids to sage that don't necessarily >> need to be managing whole worksheets much less whole notebooks. > > If nothing else, it is a really good idea, and I think something like > it would be useful. Thanks for suggesting it. > > Just out of curiosity, what do you think of this: > > http://magma.maths.usyd.edu.au/calc/ > > It wrote it years ago (before Sage), but could do a Sage version that > would be included standard in sage. > > >> >> sos >> >> On Jan 19, 10:39 pm, William Stein wrote: >>> On Mon, Jan 19, 2009 at 5:05 PM, Robert Bradshaw >>> >>> wrote: >>> >>> > On Jan 19, 2009, at 4:39 PM, Skylar wrote: >>> >>> >> I was rather hoping to keep all of the great js/css and everything >>> >> having to do with the cell like the tab completion and the way that >>> >> the input and output are handled - all are fantastic in the notebook. >>> >> I was just hoping that I could send a single cell the way that it is >>> >> displayed and functioning in the full notebook to an address/port. I >>> >> am not sure that using the simple server would be the best way to >>> >> accomplish this. >>> >>> > You're right--it would probably would be easier to try and modify the >>> > notebook to get this effect. The simple API was more designed to be a >>> > "back end" interface. >>> >>> You will probably have to copy out a bunch of javascript from >>> >>> SAGE_ROOT/devel/sage/sage/server/notebook/js.py >>> >>> in some clever way into your webpage. Then probably use >>> the simple API as the backend to actually do the work. >>> >>> To do this right would probably require some serious refactoring >>> of js.py, and at least understanding that javascript code. I'm sure >>> it could be done and that I could do it. I would estimate it would >>> take me a week of fulltime work to do this right. (I'm probably not >>> going to do this; I'm just sharing some thoughts.) >>> >>> -- William >> > >> > > > > -- > William Stein > Associate Professor of Mathematics > University of Washington > http://wstein.org > > > > --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Minimal notebook - just 1 cell
On Mon, Jan 19, 2009 at 8:32 PM, Skylar wrote: > > Well, I am certainly no javascript master. I think maybe the best > that I can do is to understand the simple server and build from there. > > Maybe I can do it in some number of months half-time. It would be a > useful adaptation to introduce kids to sage that don't necessarily > need to be managing whole worksheets much less whole notebooks. If nothing else, it is a really good idea, and I think something like it would be useful. Thanks for suggesting it. Just out of curiosity, what do you think of this: http://magma.maths.usyd.edu.au/calc/ It wrote it years ago (before Sage), but could do a Sage version that would be included standard in sage. > > sos > > On Jan 19, 10:39 pm, William Stein wrote: >> On Mon, Jan 19, 2009 at 5:05 PM, Robert Bradshaw >> >> wrote: >> >> > On Jan 19, 2009, at 4:39 PM, Skylar wrote: >> >> >> I was rather hoping to keep all of the great js/css and everything >> >> having to do with the cell like the tab completion and the way that >> >> the input and output are handled - all are fantastic in the notebook. >> >> I was just hoping that I could send a single cell the way that it is >> >> displayed and functioning in the full notebook to an address/port. I >> >> am not sure that using the simple server would be the best way to >> >> accomplish this. >> >> > You're right--it would probably would be easier to try and modify the >> > notebook to get this effect. The simple API was more designed to be a >> > "back end" interface. >> >> You will probably have to copy out a bunch of javascript from >> >> SAGE_ROOT/devel/sage/sage/server/notebook/js.py >> >> in some clever way into your webpage. Then probably use >> the simple API as the backend to actually do the work. >> >> To do this right would probably require some serious refactoring >> of js.py, and at least understanding that javascript code. I'm sure >> it could be done and that I could do it. I would estimate it would >> take me a week of fulltime work to do this right. (I'm probably not >> going to do this; I'm just sharing some thoughts.) >> >> -- William > > > -- William Stein Associate Professor of Mathematics University of Washington http://wstein.org --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Minimal notebook - just 1 cell
Well, I am certainly no javascript master. I think maybe the best that I can do is to understand the simple server and build from there. Maybe I can do it in some number of months half-time. It would be a useful adaptation to introduce kids to sage that don't necessarily need to be managing whole worksheets much less whole notebooks. sos On Jan 19, 10:39 pm, William Stein wrote: > On Mon, Jan 19, 2009 at 5:05 PM, Robert Bradshaw > > wrote: > > > On Jan 19, 2009, at 4:39 PM, Skylar wrote: > > >> I was rather hoping to keep all of the great js/css and everything > >> having to do with the cell like the tab completion and the way that > >> the input and output are handled - all are fantastic in the notebook. > >> I was just hoping that I could send a single cell the way that it is > >> displayed and functioning in the full notebook to an address/port. I > >> am not sure that using the simple server would be the best way to > >> accomplish this. > > > You're right--it would probably would be easier to try and modify the > > notebook to get this effect. The simple API was more designed to be a > > "back end" interface. > > You will probably have to copy out a bunch of javascript from > > SAGE_ROOT/devel/sage/sage/server/notebook/js.py > > in some clever way into your webpage. Then probably use > the simple API as the backend to actually do the work. > > To do this right would probably require some serious refactoring > of js.py, and at least understanding that javascript code. I'm sure > it could be done and that I could do it. I would estimate it would > take me a week of fulltime work to do this right. (I'm probably not > going to do this; I'm just sharing some thoughts.) > > -- William --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: getting output of one matrix row in two workbook lines
On Mon, Jan 19, 2009 at 11:02 AM, Mate Kosor wrote: > > I am using Sage workbook 3.2.3. in Mozilla Firefox 3.0.5 I have a > problem with matrix output. > > Line: > matrix([[diff(v_r(r, z), r), 0, diff(v_z(r, z), r)/2], [0, 0, 0],[diff > (v_z(r, z), r,)/2, 0, 0]]) > > produces output where one matrix row spans 2 rows on web browser > worksheet, like this > [ diff(v_r(r, z), r, 1) 0 diff(v_z(r, z), r, > 1)/2] > [ 0 0 > 0] > [diff(v_z(r, z), r, 1)/2 0 > 0] > > I have tried zooming out, which changes to smaller font, without > success. > > How can I get a matrix row in one line only? > Use show(foo) to typeset an output line, which won't word wrap. Or, after getting output as you do above, just click to the left of the output to toggle through: word wrap --> no word wrap --> hide William --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: number field question
On Mon, Jan 19, 2009 at 4:46 PM, Alex Raichev wrote: > > Hi everyone: > > I'm applying for a grant from the New Zealand government to fund some > Sage development in the area of computational algebraic and analytic > geometry. For part of the application i need to report on the 'state > of the field'. Part of my response to this will be to mention that > Sage doesn't have an implementation of factorization, ideal, and > variety calculations over QQbar. To double-check, is this true? > Related to that, do any major computer algebra systems (Singular > included) have such implementations? > > Alex Any commutative algebra computer computation over QQbar can be reduced to a computation over a specific absolute number field, since there are only finitely many symbols in the input to the calculation. Singular, etc., fully supports doing commutative algebra over absolute number fields. I think Singular doesn't explicitly support relative extensions, but might be able to do them anyways by just throwing in more variables. So if you're asking whether computer algebra systems such as Singular, Macaulay 2, Magma, etc., implement commutative algebra over QQbar the answer is formally "yes", in that there is a direct translation of any problem over QQbar into a problem they are designed to solve. Sage and probably the other systems are probably VERY awkward for actually doing computations over QQbar. There's a lot of bookkeeping and stuff that one would have to do, and conceptually it would be painful. Also, being able to do relative extensions is critical, since e.g., your coefficients could be the square roots of the primes up to 1000, and as an absolute field they would generate an extension of degre 2^168, which is too big. So, I'm curious, did you envision your proposal to be to automate all bookkeeping in translating between QQbar (as presented to the user) and numbers fields (as fed to the backend Singular)? I think this would be very nice and useful. - William --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Minimal notebook - just 1 cell
On Mon, Jan 19, 2009 at 5:05 PM, Robert Bradshaw wrote: > > On Jan 19, 2009, at 4:39 PM, Skylar wrote: > >> I was rather hoping to keep all of the great js/css and everything >> having to do with the cell like the tab completion and the way that >> the input and output are handled - all are fantastic in the notebook. >> I was just hoping that I could send a single cell the way that it is >> displayed and functioning in the full notebook to an address/port. I >> am not sure that using the simple server would be the best way to >> accomplish this. > > You're right--it would probably would be easier to try and modify the > notebook to get this effect. The simple API was more designed to be a > "back end" interface. You will probably have to copy out a bunch of javascript from SAGE_ROOT/devel/sage/sage/server/notebook/js.py in some clever way into your webpage. Then probably use the simple API as the backend to actually do the work. To do this right would probably require some serious refactoring of js.py, and at least understanding that javascript code. I'm sure it could be done and that I could do it. I would estimate it would take me a week of fulltime work to do this right. (I'm probably not going to do this; I'm just sharing some thoughts.) -- William --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Notebook_minimal + content management system
I am wondering if anyone on this list has managed to glue a cell of the notebook onto a content-driven web application. If anyone has any ideas on this front I would be interested to hear them. Skylar Saveland --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Minimal notebook - just 1 cell
On Jan 19, 2009, at 4:39 PM, Skylar wrote: > I was rather hoping to keep all of the great js/css and everything > having to do with the cell like the tab completion and the way that > the input and output are handled - all are fantastic in the notebook. > I was just hoping that I could send a single cell the way that it is > displayed and functioning in the full notebook to an address/port. I > am not sure that using the simple server would be the best way to > accomplish this. You're right--it would probably would be easier to try and modify the notebook to get this effect. The simple API was more designed to be a "back end" interface. - Robert --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Minimal notebook - just 1 cell
On Jan 19, 2009, at 4:27 PM, Skylar wrote: > Yes, I am starting to understand how I can use that. What are the > sleep(0.5), sleep(1)'s there for? I know that they delay execution. > I don't know exactly what that means and why it would be useful in the > code in that docstring. The sleeps are there just to give the server (which runs in a different thread in the background) time to start up. - Robert --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: number field question
Hi everyone: I'm applying for a grant from the New Zealand government to fund some Sage development in the area of computational algebraic and analytic geometry. For part of the application i need to report on the 'state of the field'. Part of my response to this will be to mention that Sage doesn't have an implementation of factorization, ideal, and variety calculations over QQbar. To double-check, is this true? Related to that, do any major computer algebra systems (Singular included) have such implementations? Alex On Dec 5 2008, 10:55 am, "William Stein" wrote: > On Thu, Dec 4, 2008 at 1:48 PM, AlexRaichev wrote: > > > Thanks for your help, Carl. Where did you find the documentation for > > the command number_field_elements_from_algebraics(c)? > > I'm guessing Carl knew about that command since he implemented it. > > Typing > > sage: help(sage.rings.qqbar) > > in Sage is pretty helpful too. > > > Yes, i'd find it very useful to have ideal and variety > > computations over QQbar implemented. I don't have the know-how or the > > time at present to do this myself, but i am learning more about Sage > > every day and my next job might support this endeavor more than my > > present one. So perhaps in the future i can work on this. > > > Alex > > Awesome. I hope you get said next job! > > -- William > > > > > > > On Dec 4, 9:31 am, Carl Witty wrote: > >> On Nov 30, 1:27 pm, AlexRaichev wrote: > > >> > > It would be helpful if you could give a more concrete example, e.g., a > >> > > session > >> > > where you have some elements, and finally want to do something with > >> > > them. > > >> > That's good idea, William. Let me back up to and change my question > >> > to a more fundamental one. How does one compute in QQbar with Sage? > >> > For example, how about factoring a polynomial, computing a radical > >> > ideal, or computing a variety (see below)? I get the same error for > >> > all these: "no conversion of this ring to a Singular ring defined". > > >> > Alex > > >> None of these things are implemented for polynomials over QQbar; and > >> as far as I know there are no plans to implement them. > > >> Simpler variants of a couple of your problems are implemented: > > >> For univariate polynomials, you can find the roots with .roots > >> (ring=QQbar), and it's trivial to compute the factorization from > >> there. > > >> You can compute the variety (over QQbar) of a zero-dimensional ideal > >> of polynomials with rational coefficients, using .variety(ring=QQbar). > > >> It would be great to have more functionality implemented for > >> polynomials over QQbar; is that something you would be interested in > >> contributing? > > >> Carl > > -- > William Stein > Associate Professor of Mathematics > University of Washingtonhttp://wstein.org --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Minimal notebook - just 1 cell
I was rather hoping to keep all of the great js/css and everything having to do with the cell like the tab completion and the way that the input and output are handled - all are fantastic in the notebook. I was just hoping that I could send a single cell the way that it is displayed and functioning in the full notebook to an address/port. I am not sure that using the simple server would be the best way to accomplish this. > Yes, use the simple api that was designed. See the doctstring at the > top ofhttp://hg.sagemath.org/sage-main/file/b0aa7ef45b3c/sage/server/ > simple/twist.py > > - Robert --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Minimal notebook - just 1 cell
Yes, I am starting to understand how I can use that. What are the sleep(0.5), sleep(1)'s there for? I know that they delay execution. I don't know exactly what that means and why it would be useful in the code in that docstring. On Jan 19, 5:52 pm, Robert Bradshaw wrote: > > Yes, use the simple api that was designed. See the doctstring at the > top ofhttp://hg.sagemath.org/sage-main/file/b0aa7ef45b3c/sage/server/ > simple/twist.py --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Finding a duplicated vector in a list of vectors
You're right. This is what I meant:
sage: L = [vector([1,0,0]), vector([1,2,0]), vector([1,0,3]), vector([1,0,0])]
sage: LL = [tuple(v.list()) for v in L]
sage: Set(LL)
{(1, 0, 0), (1, 0, 3), (1, 2, 0)}
But that is probably what you said in the first place.
Here's another idea:
sage: L = [vector([1,0,0]), vector([1,2,3]), vector([1,2,3]), vector([1,0,0])]
sage: iL = Set([L.index(v) for v in L])
sage: [L[i] for i in iL]
[(1, 0, 0), (1, 2, 3)]
Does this help in your situatiuon?
On Mon, Jan 19, 2009 at 6:26 PM, slabbe wrote:
>
>> I don't know if this is the best idea or not but I definitely have
>> run into this problem before and what I think I did was
>> to store the list of vectors as a *Set* of *lists*.
>
> Are you sure? Because as vectors, lists are unhashable :
>
> ...
> TypeError: list objects are unhashable
> >
>
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[sage-support] Re: Jordan Normal Form Problem
c mullan wrote: > Hi all, > > by general theory I know that an invertible transformation matrix P > exists such that A = ~P*J*P where J is the Jordan Normal Form of a > square matrix A. When I try to calculate P, some strange things > happen.. > > M=MatrixSpace(GF(2),7) > A=M.random_element() > f=A.charpoly() > d = lcm([p.degree() for p,e in f.factor()]) > J,P=A.jordan_form(GF(2^d,'b'),transformation=True) # in general, > A's e.values will live in an extension field > > In some instances I get an error message like: > > ValueError: cannot compute the basis of the Jordan block of size 6 > with eigenvalue 0 > Can you give a specific example of it not working, or if the above example doesn't work, exactly what you expect? When I run the above commands in 3.2.3, I get the following. Note that there was a bug in the Jordan Form code a few versions back, so you might be running into problems if you are running an old version of Sage. sage: M=MatrixSpace(GF(2),7) sage: A=M.random_element() sage: f=A.charpoly() sage: d = lcm([p.degree() for p,e in f.factor()]) sage: J,P=A.jordan_form(GF(2^d,'b'),transformation=True) sage: J [1|0|0|0 0|0 0] [-+-+-+---+---] [0|b|0|0 0|0 0] [-+-+-+---+---] [0|0|b + 1|0 0|0 0] [-+-+-+---+---] [0|0|0|0 1|0 0] [0|0|0|0 0|0 0] [-+-+-+---+---] [0|0|0|0 0|0 1] [0|0|0|0 0|0 0] sage: P [0 1 1 1 0 1 1] [1 1 1 0 0 1 0] [0 b + 1 b 1 1 1 0] [0 0 0 1 0 1 0] [1 1 1 0 1 0 1] [0 1 1 1 1 0 1] [0 1 1 1 0 0 1] Jason --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Finding a duplicated vector in a list of vectors
> I don't know if this is the best idea or not but I definitely have > run into this problem before and what I think I did was > to store the list of vectors as a *Set* of *lists*. Are you sure? Because as vectors, lists are unhashable : ... TypeError: list objects are unhashable --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Jordan Normal Form Problem
Hi all, by general theory I know that an invertible transformation matrix P exists such that A = ~P*J*P where J is the Jordan Normal Form of a square matrix A. When I try to calculate P, some strange things happen.. M=MatrixSpace(GF(2),7) A=M.random_element() f=A.charpoly() d = lcm([p.degree() for p,e in f.factor()]) J,P=A.jordan_form(GF(2^d,'b'),transformation=True) # in general, A's e.values will live in an extension field In some instances I get an error message like: ValueError: cannot compute the basis of the Jordan block of size 6 with eigenvalue 0 (nothing special about the e.value 0 here) and in other instances I get no error messages but the matrix P is singular! Can anyone see what the problem is here? Thanks. --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Minimal notebook - just 1 cell
On Jan 19, 2009, at 1:34 PM, Skylar wrote: > > Hello, > > I have been annoying the good folks of #sage-devel hoping to hack > together a way to make notebook() run but be able to retrieve just 1 > cell of a worksheet for insertion into another webpage. Does anyone > have a quick hack that I can use here? Yes, use the simple api that was designed. See the doctstring at the top of http://hg.sagemath.org/sage-main/file/b0aa7ef45b3c/sage/server/ simple/twist.py - Robert --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Finding a duplicated vector in a list of vectors
I don't know if this is the best idea or not but I definitely have run into this problem before and what I think I did was to store the list of vectors as a *Set* of *lists*. On Mon, Jan 19, 2009 at 4:43 PM, slabbe wrote: > > PROBLEM : > In a list of vectors, I want to know if there is a pair of equal > vectors. > > I have two solutions. The first to create an empty list L and append > the vectors one per one. If a vector is already in L before adding it, > then I found a pair of equal vectors. But looking if a vector belongs > to a list is apparently very slow on my computer : > > sage: v = vector((1, SR(0))) > sage: w = vector((1, sqrt(2))) > sage: time v in [v,v,v,v,v,v,v,v,v] > CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s > Wall time: 0.00 s > True > sage: time w in [v] > CPU times: user 0.92 s, sys: 0.20 s, total: 1.12 s > Wall time: 5.17 s > False > sage: time w in [v,v] > CPU times: user 1.86 s, sys: 0.46 s, total: 2.32 s > Wall time: 12.32 s > False > sage: time w in [v,v,v,v] > CPU times: user 4.83 s, sys: 1.14 s, total: 5.97 s > Wall time: 32.42 s > False > > My second solution is to put them in a set. But since vectors are not > hashable, I first convert them into tuples. But I then get two equal > vectors having distinct hash values: > > sage: z = vector((1,sqrt(2)-sqrt(2))); z > (1, 0) > sage: v = vector((1, SR(0))) ; v > (1, 0) > sage: z == v > True > sage: tuple(z) == tuple(v) > True > sage: hash(tuple(z)) > -1374268819 > sage: hash(tuple(v)) > 1302034650 > sage: map(type, z) > [, > ] > sage: map(type, v) > [, > ] > > Anybody has a better idea? > > Thank you > > Sébastien Labbé > > > > --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Finding a duplicated vector in a list of vectors
PROBLEM : In a list of vectors, I want to know if there is a pair of equal vectors. I have two solutions. The first to create an empty list L and append the vectors one per one. If a vector is already in L before adding it, then I found a pair of equal vectors. But looking if a vector belongs to a list is apparently very slow on my computer : sage: v = vector((1, SR(0))) sage: w = vector((1, sqrt(2))) sage: time v in [v,v,v,v,v,v,v,v,v] CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s Wall time: 0.00 s True sage: time w in [v] CPU times: user 0.92 s, sys: 0.20 s, total: 1.12 s Wall time: 5.17 s False sage: time w in [v,v] CPU times: user 1.86 s, sys: 0.46 s, total: 2.32 s Wall time: 12.32 s False sage: time w in [v,v,v,v] CPU times: user 4.83 s, sys: 1.14 s, total: 5.97 s Wall time: 32.42 s False My second solution is to put them in a set. But since vectors are not hashable, I first convert them into tuples. But I then get two equal vectors having distinct hash values: sage: z = vector((1,sqrt(2)-sqrt(2))); z (1, 0) sage: v = vector((1, SR(0))) ; v (1, 0) sage: z == v True sage: tuple(z) == tuple(v) True sage: hash(tuple(z)) -1374268819 sage: hash(tuple(v)) 1302034650 sage: map(type, z) [, ] sage: map(type, v) [, ] Anybody has a better idea? Thank you Sébastien Labbé --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Minimal notebook - just 1 cell
Hello, I have been annoying the good folks of #sage-devel hoping to hack together a way to make notebook() run but be able to retrieve just 1 cell of a worksheet for insertion into another webpage. Does anyone have a quick hack that I can use here? Thank you, Skylar Saveland --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] getting output of one matrix row in two workbook lines
I am using Sage workbook 3.2.3. in Mozilla Firefox 3.0.5 I have a problem with matrix output. Line: matrix([[diff(v_r(r, z), r), 0, diff(v_z(r, z), r)/2], [0, 0, 0],[diff (v_z(r, z), r,)/2, 0, 0]]) produces output where one matrix row spans 2 rows on web browser worksheet, like this [ diff(v_r(r, z), r, 1) 0 diff(v_z(r, z), r, 1)/2] [ 0 0 0] [diff(v_z(r, z), r, 1)/2 0 0] I have tried zooming out, which changes to smaller font, without success. How can I get a matrix row in one line only? --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: lost connection to maxima
On Jan 19, 10:07 am, "ma...@mendelu.cz" wrote: > On 14 Led, 08:50, mabshoff Hi Robert, > To finish this thread: I had another lecture in computer lab today. We > had 2GB RAM, very very big swap and 15 rather slow students with > allmost no experiences with computer algebra systems ( = short > worksheets and not many requests in short time). No problem occured > today. Thanks for the update. Please let us know if you run into any more trouble or want to share more of your experience with Sage with us. > I hope, this information could be usefull for some other educators > using sage. > > Thank you for your help. > > Robert M. Cheers, Michael --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: lost connection to maxima
On 14 Led, 08:50, mabshoff wrote: > > Your server calls Maxima and without taking a closer look it is > unclear to me if you start a Maxima process per user or not. Overall > Maxima is lighter than Sage primarily because it is all common lisp > and does not use any external libraries per default, which is one of > the reasons Sage's memory footprint is larger than Maxima's. OTOH > Maxima is missing a lot of he functionality that Sage provides, but > the price we pay for that is a larger footprint. So if you were to use > Sage "just" as a tool to do calculus (which is mostly handled by > Maxima at the moment) we cannot be less large than Maxima by itself :) To finish this thread: I had another lecture in computer lab today. We had 2GB RAM, very very big swap and 15 rather slow students with allmost no experiences with computer algebra systems ( = short worksheets and not many requests in short time). No problem occured today. I hope, this information could be usefull for some other educators using sage. Thank you for your help. Robert M. --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: graph.automorphism_group(translation=True) gives error in 3.2.3
Nikos, > It seems that when the vertices are labelled 0,..., n-1 then the > translation is simply 0 <-> n, and the rest is fixed. At least > this is the case with all examples I've seen. Can I assume that > this will allways be the case? This is what happens. At first, the graph calls its relabel command with no arguments. See sage: G.relabel?? to see exactly what goes on there. --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: unstable modules + creating a small library
On Jan 19, 6:28 am, Pierre wrote: > hi all > > I've just realized that SAGE knows about the Steenrod algebra now. > Does it know about unstable modules, too ? No, it doesn't, unfortunately. (Sage doesn't know about tensor products, which has delayed me from implementing various things, like the coproduct, and I suppose modules.) > I have another, related question. I have computed the unstable module > structure on the mod 2 cohomology rings of quite a bunch of finite > groups, see > > http://www-irma.u-strasbg.fr/~guillot/research/cohomology_of_groups/i... This looks very nice. > I was thinking that I should, somehow, provide a file readable by SAGE > so that people could use these algebras. Sure. > For one thing it would > provide many examples of unstable modules, which is always good to > test ideas about the Steenrod algebra. And regardless of the steenrod > operations, even the cohomology rings, as computed by Carlson and > others, are not available in SAGE yet (they're there as Magma files). > At this point I can relatively easily provide a partial translation > into SAGE. I think Simon King does some group cohomology computations with Sage, but I don't know exactly how he does it. > However I was wondering about the best "format" for this: assuming the > unstable algebra class does not exist, shall I present the algebras as > quotients of polynomial rings ? or just give a couple of SAGE lists > with the generators and relations, possibly just members of the formal > ring ? or something pickled perhaps ? I really don't know. Note that > I've got more information on these algebras yet (Stiefel-Whitney > classes...) It sounds to me as though you should create a new class, the UnstableAlgebra class, or the ModularGroupCohomology class, or something, which should derive from the class of quotients of polynomial algebras (so you can define at least part of the structure by specifying such a quotient), and then there should be extra structure: the Steenrod operations and Stiefel-Whitney classes and whatever else you have. > And shall I think of a mechanism for people to download ALL the > examples at once rather than separately ? (perhaps useful to try a > conjecture about unstable modules ?) You might have two files: one which defines the class, and another which presents all of the examples. I haven't used databases in Sage, but perhaps the examples could be a dictionary indexed by the group, or something like that? I'm looking forward to whatever you come up with. John Palmieri > suggestions most welcome. > Thanks, > > pierre --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Operator for Function Composition
> > With an operator (say @@) for iterated composition, > I could write simply instead: > > sage: f = lambda e: integrate(e,x) > sage: (f @@ 4)(_) I will ask the stupid question: Can SymbolicComposition etc. in the calculus module be used for this after making something symbolic? (My guess is no, since it wasn't brought up.) FWIW, - kcrisman --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] unstable modules + creating a small library
hi all I've just realized that SAGE knows about the Steenrod algebra now. Does it know about unstable modules, too ? I have another, related question. I have computed the unstable module structure on the mod 2 cohomology rings of quite a bunch of finite groups, see http://www-irma.u-strasbg.fr/~guillot/research/cohomology_of_groups/index.html I was thinking that I should, somehow, provide a file readable by SAGE so that people could use these algebras. For one thing it would provide many examples of unstable modules, which is always good to test ideas about the Steenrod algebra. And regardless of the steenrod operations, even the cohomology rings, as computed by Carlson and others, are not available in SAGE yet (they're there as Magma files). At this point I can relatively easily provide a partial translation into SAGE. However I was wondering about the best "format" for this: assuming the unstable algebra class does not exist, shall I present the algebras as quotients of polynomial rings ? or just give a couple of SAGE lists with the generators and relations, possibly just members of the formal ring ? or something pickled perhaps ? I really don't know. Note that I've got more information on these algebras yet (Stiefel-Whitney classes...) And shall I think of a mechanism for people to download ALL the examples at once rather than separately ? (perhaps useful to try a conjecture about unstable modules ?) suggestions most welcome. Thanks, pierre --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
