[sage-support] instance returns False after modifying file

2012-03-24 Thread tvn
This seems to be a very weird behavior. After modifying a file, all instantiated instances V of classes C in the file are no longer correct (i.e. instance(V,C) returns false). Here's a simple example illustrating the problem I have a file called t1.py contains the following class

Re: [sage-support] instance returns False after modifying file

2012-03-24 Thread Justin C. Walker
On Mar 24, 2012, at 11:31 , tvn wrote: This seems to be a very weird behavior. After modifying a file, all instantiated instances V of classes C in the file are no longer correct (i.e. instance(V,C) returns false). Here's a simple example illustrating the problem [snip] Now go

Re: [sage-support] instance returns False after modifying file

2012-03-24 Thread William Stein
On Mar 24, 2012 2:46 PM, Justin C. Walker jus...@mac.com wrote: On Mar 24, 2012, at 11:31 , tvn wrote: This seems to be a very weird behavior. After modifying a file, all instantiated instances V of classes C in the file are no longer correct (i.e. instance(V,C) returns false).

[sage-support] Bug in edge_cut of undirected weighted graphs

2012-03-24 Thread Stephen Hartke
While generating subtour elimination constraints for a traveling salesman problem, I bound a bug in the edge_cut method for undirected weighted graphs. Specifically, when using the Ford-Fulkerson method, the value of the minimum cut is correct, but sometimes the returned edge cut does not have

Re: [sage-support] Bug in edge_cut of undirected weighted graphs

2012-03-24 Thread D. S. McNeil
I think I have a smaller example: sage: G = Graph([(0, 3, 1), (0, 4, 1), (1, 2, 1), (2, 3, 1), (2, 4, 1)]) sage: G.edge_cut(0,1,value_only=False,use_edge_labels=True) [1, [(0, 3, 1), (1, 2, 1), (2, 3, 1)]] sage: G.edge_cut(0,1,value_only=False,use_edge_labels=True,method='LP') (1.0, [(1, 2)])

[sage-support] Univariate Polynomial Creation

2012-03-24 Thread Ben
Intel Ubuntu 11.10 Sage 4.8 When you enter: PolynomialRing(QQ,1,'y') or R.y=PolynomialRing(QQ,1) returns a multivariable polynomial ring. Whereas PolynomialRIng(QQ,'y') or R.y=PolynomialRing(QQ) returns a univariate polynomial ring. I am using this in Affine Space. For example,

[sage-support] Re: Using Python new style string formatting in Sage

2012-03-24 Thread Zoresvit
Thanks a lot! Always forgetting Sage has its own type for integers. Some automatic coersion would help a lot in such situation. On Wednesday, March 7, 2012 2:02:17 PM UTC+2, Jason Grout wrote: On 3/7/12 5:50 AM, Zoresvit wrote: Is there a way to use new Python string formatting

[sage-support] Re: Weird behaviour in integrate code

2012-03-24 Thread ancienthart
Hi kcrisman, just some followups: Have added the following to ask.sagemath.org http://ask.sagemath.org/question/1265/how-to-dynamically-substitute-a-variable-in-a Have applied the http://trac.sagemath.org/sage_trac/ticket/11143 patch (along with this patch as well

[sage-support] Re: Weird behaviour in integrate code

2012-03-24 Thread ancienthart
Or rather, the limit syntax seems to be completely out of whack. This seems to be promising, except that minus needs to be replaced by -Infinity, and then I get an error message relating to the limit function. -- To post to this group, send email to sage-support@googlegroups.com To

[sage-support] Does the email function need to be configured?

2012-03-24 Thread Starx
The documentation for the email function seems to indicate that it should work out of the box so to speak. I tried sending myself an email using the command sage: email('myem...@mydomain.com', 'Test subject', 'Test body!') I tried this on 4.8 and got an error, tried this on beta7 and didn't get