[sage-support] Re: Using multiple cores with Sage under VMWare Player
> > Here's a really dumb thing you could do. > > (1) Make a copy of sage-vmware-* to another directory. > > (2) Run both vmware's at the same time. > > That'll definitely use both cores on your computer. Indeed! That's what I ended up doing this afternoon. I had VMWare Workstation make a clone of my Sage virtual machine. For some reason, when I tried simply making a copy of Sage in another directory (before I tried Workstation), I couldn't get it to run. Whenever I tried to start it up a second copy, something would flash on the screen, vanishing before I could read it, and the notebook system would not run. Probably I was doing something foolish. Is there any direct way to share Sage worksheets between two virtual machines, or is it simplest to save the files from one system and load them into another? Thanks again, James Parson --~--~-~--~~~---~--~~ 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: Coercion into power series ring
I tried change_ring(), without success... sage: R.=PowerSeriesRing(QQ) sage: P.=PolynomialRing(R) sage: f=t*x+t^2 sage: g=f/t sage: f t*x + t^2 sage: g x + t sage: f.parent() Univariate Polynomial Ring in x over Power Series Ring in t over Rational Field sage: g.parent() Univariate Polynomial Ring in x over Laurent Series Ring in t over Rational Field sage: g.change_ring(R) --- TypeError Traceback (most recent call last) ... TypeError: Unable to coerce t () to Rational sage: Now I am forced to extract coefficients of g, and reconstruct g with the right base ring. Or I may live with laurent series base ring. --~--~-~--~~~---~--~~ 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: Using multiple cores with Sage under VMWare Player
2009/6/8 James Parson : > >> You might have to use vmware workstation in order to configure the >> virtual machine to use more than 1 core: >> >> http://www.vmware.com/products/ws/ >> >> It costs money, but there is an easy 1-month free trial. You could try >> that in order to tell whether multiple cores will work with the >> virtual machine. > > Thanks for your suggestion. I downloaded the trial version of > Workstation, and I was able to change a "Processor" setting so that > VMWare Workstation said that it was using 2 processors. Even after > that change, though, if I started two worksheets with independent > calculations, they still ran on just one core. Do you have any other > thoughts? > Here's a really dumb thing you could do. (1) Make a copy of sage-vmware-* to another directory. (2) Run both vmware's at the same time. That'll definitely use both cores on your computer. 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: Folders to organise worksheets
On Jun 4, 9:44 am, William Stein wrote: > On Thu, Jun 4, 2009 at 1:36 AM, kilucas wrote: > > > As a set of worksheets grows I feel I need to organise them into my > > own folder structure. On sagenb I can see Active, Archived and Trash > > folders for worksheets but can't spot a way to create my own folders > > or navigate such a folder structure afterwards. Can I do this (and > > especially - can I do this as an online worksheet user without > > resorting to to the sage command line) and if so how please? Or should > > I organise my worksheets in some other way perhaps? > > Unfortunately, there is currently no support for folders in the Sage > notebook. Nobody has had a chance to implement it yet. However, > Mike Hansen is currently planning to implement both folders and labels > for the Sage notebook in the immediate future. > > So stay tuned! > > In the meantime, I tend to put a keyword in the title of a collection > of related worksheets, then use the search box in the upper right to > view only those worksheets. > V helpful. Thanks. > William > > > > > Many thanks for any clues you can give. > > > Kevin > > -- > 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: element-wise multiplication of matrices
kcrisman wrote: > > >> This is based on the code developed in the >> threadhttp://groups.google.com/group/sage-devel/browse_thread/thread/100de8... >> >> (that code probably should get into Sage; it makes some calculations >> very, very easy to write down...) >> >> The trac ticket for incorporating this decorator >> ishttp://trac.sagemath.org/sage_trac/ticket/6245 > > There are lots of good uses for something like this, e.g. I could have > used this for teaching Dirichlet products this past semester. If > something like this ever got into Sage, would it only be for "private" If you polish it up into a patch, I'll review it (so hopefully it gets into 4.0.2)! Hmmm...or maybe I shouldn't review it, being one of the authors... > use as detailed above, or could some custom infix operators > potentially become standard like the backslash, which only works for > things with the _backslash_ defined (presumably only matrix/vector > combos)? Only time will tell. I think it's safe to say it would be available for private use. Frankly, I'm a bit surprised that we have the backslash operator. It's a bow to matlab (I assume), but there are lots and lots of other matlab operators we don't have. Sage has (rightfully) been very conservative about language additions. However, I can see a sage.misc.infix module (or even specific modules, like sage.graphs.infix) containing a bunch of nice infix operators, not defined by default, but that someone could then import. That would help standardize some things if people used them a lot. Jason -- Jason Grout --~--~-~--~~~---~--~~ 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] sage -t problems with semicolons and line breaks
On the file test.py, consisting of
"""
EXAMPLES::
sage: gcd(4,6);
sage: a = {1:'a',
2:'b'}
"""
running sage -t produces two error messages (see below). Is it true
that sage -t does not recognize semicolons and does not parse line
breaks correctly? (Cutting and pasting the code in the examples into
sage produces no errors.)
Thanks,
Dave
| Sage Version 4.0.alpha0, Release Date: 2009-05-15
sage -t "test.py"
**
File "/home/davidp/math/sandpile/sage/sage-sandpile1.4/test.py", line
4:
sage: gcd(4,6);
Expected nothing
Got:
2
**
File "/home/davidp/math/sandpile/sage/sage-sandpile1.4/test.py", line
5:
e: a = {1:'a',
Exception raised:
Traceback (most recent call last):
File "/home/davidp/download/sage-devel/local/bin/ncadoctest.py",
line 1231, in run_one_test
self.run_one_example(test, example, filename, compileflags)
File "/home/davidp/download/sage-devel/local/bin/
sagedoctest.py", line 38, in run_one_example
OrigDocTestRunner.run_one_example(self, test, example,
filename, compileflags)
File "/home/davidp/download/sage-devel/local/bin/ncadoctest.py",
line 1172, in run_one_example
compileflags, 1) in test.globs
File "", line 1
a = {Integer(1):'a',###line 5:
e: a = {1:'a',
^
SyntaxError: unexpected EOF while parsing
**
1 items had failures:
2 of 4 in __main__.example_0
***Test Failed*** 2 failures.
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[sage-support] Re: element-wise multiplication of matrices
> This is based on the code developed in the > threadhttp://groups.google.com/group/sage-devel/browse_thread/thread/100de8... > > (that code probably should get into Sage; it makes some calculations > very, very easy to write down...) > > The trac ticket for incorporating this decorator > ishttp://trac.sagemath.org/sage_trac/ticket/6245 There are lots of good uses for something like this, e.g. I could have used this for teaching Dirichlet products this past semester. If something like this ever got into Sage, would it only be for "private" use as detailed above, or could some custom infix operators potentially become standard like the backslash, which only works for things with the _backslash_ defined (presumably only matrix/vector combos)? - 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] Re: Using multiple cores with Sage under VMWare Player
> You might have to use vmware workstation in order to configure the > virtual machine to use more than 1 core: > > http://www.vmware.com/products/ws/ > > It costs money, but there is an easy 1-month free trial. You could try > that in order to tell whether multiple cores will work with the > virtual machine. Thanks for your suggestion. I downloaded the trial version of Workstation, and I was able to change a "Processor" setting so that VMWare Workstation said that it was using 2 processors. Even after that change, though, if I started two worksheets with independent calculations, they still ran on just one core. Do you have any other thoughts? Thanks again, James Parson --~--~-~--~~~---~--~~ 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: Removing objects from lists; keeping original list unchanged?
On Jun 8, 2009, at 06:44 , Alasdair wrote: > This is more of a python question than a Sage question, but > anyway... FYI, the Python site has plenty of documentation; the Library reference manual would have provided the answer. > I'm trying to iterate over a list, producing a sequence of > new lists, each of which is obtained from the original list by > deleting one object. I've tried: > > for x in lst: > lstc=copy(lst) > print lstc.remove(x) > > But this doesn't work - can anybody tell me what I'm doing wrong, and > what I should be doing? The first thing to know is that it helps us to diagnose the problems you are having if you provide some indication of what "it doesn't work" means. In particular, what is not happening that should, or what is happening that should not. > I can get the effect I want by iterating over > the indices of the list, but I'd like to know why this little snippet > of code doesn't work. You are incorrectly assuming that lstc.remove() returns a value. It does not. The remove() method modifies the input list. This should do what you want: for x in lst: lstc = copy(lst) lstc.remove(x) print lstc HTH Justin -- Justin C. Walker Curmudgeon-at-large Director Institute for the Absorption of Federal Funds 186,000 Miles per Second Not just a good idea: it's the law! --~--~-~--~~~---~--~~ 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: Removing objects from lists; keeping original list unchanged?
Thanks for that! Only a little thing, but I was getting very confused. -A. On Jun 9, 12:01 am, Jason Bandlow wrote: > Alasdair wrote: > > This is more of a python question than a Sage question, but > > anyway...I'm trying to iterate over a list, producing a sequence of > > new lists, each of which is obtained from the original list by > > deleting one object. I've tried: > > > for x in lst: > > lstc=copy(lst) > > print lstc.remove(x) > > > But this doesn't work - can anybody tell me what I'm doing wrong, and > > what I should be doing? I can get the effect I want by iterating over > > the indices of the list, but I'd like to know why this little snippet > > of code doesn't work. > > The problem is that > > lstc.remove(x) > > modifies lstc in place and doesn't return anything. So you aren't > printing anything. The following should do what you want: > > for x in lst: > lstc = copy(lst) > lstc.remove(x) > print lstc > > HTH, > Jason --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "sage-support" group. 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?hl=en -~--~~~~--~~--~--~---
[sage-support] Re: Removing objects from lists; keeping original list unchanged?
Hi Alasdair, I understand that you mean sage: lst=[[1,2],[3,4],[5,6]] sage: for x in lst: : lstc=copy(lst) : lstc.remove(x) : print lstc : [[3, 4], [5, 6]] [[1, 2], [5, 6]] [[1, 2], [3, 4]] Probably you got onle "None" printed. This is because the return value of lstc.remove(x) is None. The remove() method changes the list in place. Best regards, Simon --~--~-~--~~~---~--~~ 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: Removing objects from lists; keeping original list unchanged?
Alasdair wrote: > This is more of a python question than a Sage question, but > anyway...I'm trying to iterate over a list, producing a sequence of > new lists, each of which is obtained from the original list by > deleting one object. I've tried: > > for x in lst: >lstc=copy(lst) >print lstc.remove(x) > > But this doesn't work - can anybody tell me what I'm doing wrong, and > what I should be doing? I can get the effect I want by iterating over > the indices of the list, but I'd like to know why this little snippet > of code doesn't work. The problem is that lstc.remove(x) modifies lstc in place and doesn't return anything. So you aren't printing anything. The following should do what you want: for x in lst: lstc = copy(lst) lstc.remove(x) print lstc HTH, 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] Removing objects from lists; keeping original list unchanged?
This is more of a python question than a Sage question, but anyway...I'm trying to iterate over a list, producing a sequence of new lists, each of which is obtained from the original list by deleting one object. I've tried: for x in lst: lstc=copy(lst) print lstc.remove(x) But this doesn't work - can anybody tell me what I'm doing wrong, and what I should be doing? I can get the effect I want by iterating over the indices of the list, but I'd like to know why this little snippet of code doesn't work. Thanks, Alasdair --~--~-~--~~~---~--~~ 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: Coercion into power series ring
A comparable case works well. sage: S.=ZZ[] sage: f=2*x+4; sage: f/2 x + 2 sage: S(f/2).parent() Univariate Polynomial Ring in x over Integer Ring --~--~-~--~~~---~--~~ 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: Sage 4.0 can be installed on ubuntu 8.04?
On 8 juin, 03:25, Bruce Cohen wrote: > I installed this binary: > sage-4.0-linux-Debian_GNU_Linux_4.0_etch-sse2-i686-Linux > on my ubuntu 8.04 machine. For information : wich processor ? how many RAM ? --~--~-~--~~~---~--~~ 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: element-wise multiplication of matrices
Dan Drake wrote:
> On Sun, 07 Jun 2009 at 11:12AM -0700, paramaniac wrote:
>> Is there a possibility/workaround in Sage to compute the element-wise
>> multiplication of two matrices? In Matlab there's the .* operator, but
>> Matlab is useless in my case since I need a symbolic result.
>
> There's no operator that I know of for that, but you can convert your
> matrices to lists, multiply, and convert back:
>
> sage: x,y,z,w = var('x y z w')
> sage: a = matrix(SR, 2, 2, [x, y, z, w])
> sage: b = matrix(SR, 2, 2, [1+x, 1+y, 1+z, 1+w])
> sage: a.list()
> [x, y, z, w]
> sage: b.list()
> [x + 1, y + 1, z + 1, w + 1]
>
> Now make a list of corresponding pairs of entries with zip() and
> multiply:
>
> sage: [ x*y for x, y in zip(a.list(), b.list()) ]
> [(x + 1)*x, (y + 1)*y, (z + 1)*z, (w + 1)*w]
>
> ...and make a matrix out of the new list:
>
> sage: matrix(2, 2, [ x*y for x, y in zip(a.list(), b.list()) ])
>
> [(x + 1)*x (y + 1)*y]
> [(z + 1)*z (w + 1)*w]
>
> You can easily put that sequence of steps into a function. You may need
> to fiddle a bit with the rows and columns bits, and maybe add a ring
> argument if you need to specify what ring the matrix should be over.
>
> def componentwise_multiply(a, b, rows, cols):
> return matrix(rows, cols, [x*y for x, y in zip(a.list(), b.list())])
You can also turn this into a custom infix operator, if you want. That
would mean that your code would depend on a definition, but it could
make your function a lot easier to use. See
http://sagenb.org/home/pub/565 for an example using the above code.
This is based on the code developed in the thread
http://groups.google.com/group/sage-devel/browse_thread/thread/100de89e7d402134/fe89570b403344ae
(that code probably should get into Sage; it makes some calculations
very, very easy to write down...)
The trac ticket for incorporating this decorator is
http://trac.sagemath.org/sage_trac/ticket/6245
Thanks,
Jason
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[sage-support] code breakage due to upgrade to sage 4.0
Dear all,
I noticed that some of my old code does not work any more with sage
4.0.
I used to assign the solutions of equations by referring to them in
the following way:
--
| Sage Version 4.0, Release Date: 2009-05-29 |
| Type notebook() for the GUI, and license() for information.|
--
sage: var('x y')
(x, y)
sage: soln = solve(y == x^3 -2, x)
sage: x1 = soln[0][2]
---
TypeError Traceback (most recent call
last)
/Users/sschym/ in ()
TypeError: 'sage.symbolic.expression.Expression' object is unindexable
This works now:
sage: x1 = soln[0].rhs()
sage: x1
1/2*(I*sqrt(3) - 1)*(y + 2)^(1/3)
Is there a way to make soln[0][2] work again? Otherwise I would have
to change most of my notebooks!
Another issue is that the substitute command now expects dictionary
entries without quotations, so that my previous use of the subs
command does not work any more:
sage: pars = dict(y=2)
sage: pars
{'y': 2}
sage: x1.subs(pars)
---
TypeError Traceback (most recent call
last)
...
This works now:
sage: x1.subs({y:2})
1/2*(I*sqrt(3) - 1)*4^(1/3)
Is there an easy way of getting my old notebooks to work with Sage
4.0? Is there an easy way to create dictionaries without the
quotations for use in subs()??
Thanks for your help!
Stan
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[sage-support] Coercion into power series ring
Hi, See this: sage: R.=PowerSeriesRing(QQ) sage: P.=PolynomialRing(R) sage: f=(x*t+t^2)/t sage: f x + t sage: P(f) --- TypeError Traceback (most recent call last) ... TypeError: Unable to coerce t () to Rational sage: f.parent() Univariate Polynomial Ring in x over Laurent Series Ring in t over Rational Field What is a convenient way to coerce f into P? Kwankyu --~--~-~--~~~---~--~~ 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: element-wise multiplication of matrices
Thank you for the fast response! Regards, Lukas --~--~-~--~~~---~--~~ 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: element-wise multiplication of matrices
Thank you for the fast response! Regards, Lukas --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
