Re: Issue 3669 in sympy: rsolve(F(n) + F(n - 2) + F(n - 1),F(n)) return 0

2013-02-27 Thread sympy
Updates: Status: Fixed Comment #2 on issue 3669 by smi...@gmail.com: rsolve(F(n) + F(n - 2) + F(n - 1),F(n)) return 0 http://code.google.com/p/sympy/issues/detail?id=3669 (No comment was entered for this change.) -- You received this message because this project is configured to

Re: Issue 3671 in sympy: logcombine(log(x) - log(2)) doesn't work

2013-02-27 Thread sympy
Comment #3 on issue 3671 by smi...@gmail.com: logcombine(log(x) - log(2)) doesn't work http://code.google.com/p/sympy/issues/detail?id=3671 Sorry...only in the case of a Rational will it split off the denominator. The reason it is not working in logcombine is that -log(2) is a Mul and is

Re: Issue 3671 in sympy: logcombine(log(x) - log(2)) doesn't work

2013-02-27 Thread sympy
Comment #4 on issue 3671 by asmeu...@gmail.com: logcombine(log(x) - log(2)) doesn't work http://code.google.com/p/sympy/issues/detail?id=3671 Ah, and if it combines the coefficient into an exponent, in that case it does go back. So maybe logcombine should work with a dummy class that

Re: Issue 2015 in sympy: Hangs attempting to solve a system of linear equations

2013-02-27 Thread sympy
Comment #20 on issue 2015 by matt...@gmail.com: Hangs attempting to solve a system of linear equations http://code.google.com/p/sympy/issues/detail?id=2015 I did some experimentation and using solve_lin_sys() from #1850 and sparse rational functions from sparse-polys branch I was able to

Re: Issue 2015 in sympy: Hangs attempting to solve a system of linear equations

2013-02-27 Thread sympy
Comment #21 on issue 2015 by asmeu...@gmail.com: Hangs attempting to solve a system of linear equations http://code.google.com/p/sympy/issues/detail?id=2015 That's great. Aside from the basic slowdown of the dense representation for multivariate polynomials, and the infamous expand call,

Issue 3672 in sympy: factorint should reject bad input

2013-02-27 Thread sympy
Status: Valid Owner: Labels: Type-Defect Priority-Medium EasyToFix New issue 3672 by smi...@gmail.com: factorint should reject bad input http://code.google.com/p/sympy/issues/detail?id=3672 factorint(log(42)) {3: 1} Hmm... -- You received this message because this project is configured

Re: Issue 3671 in sympy: logcombine(log(x) - log(2)) doesn't work

2013-02-27 Thread sympy
Comment #5 on issue 3671 by smi...@gmail.com: logcombine(log(x) - log(2)) doesn't work http://code.google.com/p/sympy/issues/detail?id=3671 Also, there is no reason to disable the joining of vanilla x with 2: log(x) - log(2) should always be the same as log(x/2), I believe, since the

Re: Issue 3671 in sympy: logcombine(log(x) - log(2)) doesn't work

2013-02-27 Thread sympy
Updates: Status: Started Comment #6 on issue 3671 by smi...@gmail.com: logcombine(log(x) - log(2)) doesn't work http://code.google.com/p/sympy/issues/detail?id=3671 Although I haven't implemented the combining of a single vanilla term with others, I have used what I've learned in

Issue 3673 in sympy: conversion

2013-02-27 Thread sympy
Status: New Owner: Labels: Type-Defect Priority-Medium Matrices New issue 3673 by eumod...@gmail.com: conversion http://code.google.com/p/sympy/issues/detail?id=3673 The null space is of dimension 2x5 It comes as a list Converting it to a matrix results a vector instead of a list A_s

Re: Issue 3667 in sympy: getting consistent output from solve until a Solution class is available

2013-02-27 Thread sympy
Updates: Summary: getting consistent output from solve until a Solution class is available Comment #4 on issue 3667 by smi...@gmail.com: getting consistent output from solve until a Solution class is available http://code.google.com/p/sympy/issues/detail?id=3667 OK, I see. When

Re: Issue 3560 in sympy: solve() is a giant mess

2013-02-27 Thread sympy
Comment #17 on issue 3560 by smi...@gmail.com: solve() is a giant mess http://code.google.com/p/sympy/issues/detail?id=3560 To get consistent output (until everything is rewritten some day) the `dict=True` option will give you a list of dictionaries (see issue 3667) -- You received this

Issue 3674 in sympy: allow removal of -1 by some sort of factoring

2013-02-27 Thread sympy
Status: Valid Owner: Labels: Type-Defect Priority-Medium New issue 3674 by smi...@gmail.com: allow removal of -1 by some sort of factoring http://code.google.com/p/sympy/issues/detail?id=3674 Although a negative Integer can be factored out of an expression, none of factor,

Re: Issue 161 in sympy: writing a Mathematica parser

2013-02-27 Thread sympy
Comment #15 on issue 161 by matt...@gmail.com: writing a Mathematica parser http://code.google.com/p/sympy/issues/detail?id=161 Last year I wrote a Mathematica parser in Scala (https://github.com/mattpap/mathematica-parser). It supports most commonly used syntax, but has problems with nasty

Re: Issue 161 in sympy: writing a Mathematica parser

2013-02-27 Thread sympy
Updates: Labels: Parsing Comment #16 on issue 161 by asmeu...@gmail.com: writing a Mathematica parser http://code.google.com/p/sympy/issues/detail?id=161 Cool. We will need to work out a good framework for parsers in SymPy, so that we can have parsers for many languages without too

Re: Issue 161 in sympy: writing a Mathematica parser

2013-02-27 Thread sympy
Comment #17 on issue 161 by matt...@gmail.com: writing a Mathematica parser http://code.google.com/p/sympy/issues/detail?id=161 There is some documentation, but it isn't very helpful when you try to write a parser. -- You received this message because this project is configured to send all

Re: Issue 3017 in sympy: Eq,Ne.doit() don't do it

2013-02-27 Thread sympy
Comment #5 on issue 3017 by asmeu...@gmail.com: Eq,Ne.doit() don't do it http://code.google.com/p/sympy/issues/detail?id=3017 Oh, I see it's just doit, not automatically. Still, it's a can of worms if we don't have a good separation of boolean and symbolic Eq. -- You received this message

Re: Issue 3511 in sympy: SymPy is not easy_installable

2013-02-27 Thread sympy
Comment #1 on issue 3511 by asmeu...@gmail.com: SymPy is not easy_installable http://code.google.com/p/sympy/issues/detail?id=3511 Good news! There is an active discussion to completely remove the link crawling behavior of pip/easy_install, see

Re: Issue 3615 in sympy: Test failure with numpy 1.7.0

2013-02-27 Thread sympy
Updates: Status: Started Comment #6 on issue 3615 by asmeu...@gmail.com: Test failure with numpy 1.7.0 http://code.google.com/p/sympy/issues/detail?id=3615 We just needed to bump up our Matrix.__array_priority__, which was set to 10. See https://github.com/sympy/sympy/pull/1846.

Re: Issue 3673 in sympy: Matrices of matrices

2013-02-27 Thread sympy
Comment #2 on issue 3673 by mrock...@gmail.com: Matrices of matrices http://code.google.com/p/sympy/issues/detail?id=3673 Now, A_null is basically [matrix1, matrix2], so shouldn't it also put matrix1 on top of matrix2? Maybe try [[matrix1], [matrix2]] what is that supposed to be, some kind

Re: Issue 3511 in sympy: SymPy is not easy_installable

2013-02-27 Thread sympy
Comment #2 on issue 3511 by asmeu...@gmail.com: SymPy is not easy_installable http://code.google.com/p/sympy/issues/detail?id=3511 And for those curious about actual work being done: https://github.com/pypa/pip/issues/818. -- You received this message because this project is configured

Re: Issue 2015 in sympy: Hangs attempting to solve a system of linear equations

2013-02-27 Thread sympy
Comment #22 on issue 2015 by matt...@gmail.com: Hangs attempting to solve a system of linear equations http://code.google.com/p/sympy/issues/detail?id=2015 I pushed the experimental solver to sparse-polys and reduced computation times to 0.35 and 1.1 seconds (simplified, original). --

Re: [sympy] generating difference equations

2013-02-27 Thread someone
But if all it is is converting a Derivative into some expression, couldn't the whole thing be done with a single call to .replace()? I suppose things get a little more tricky than that for higher order derivatives, but not by much. I think that the original idea was to *generate* the

Re: [sympy] Re: Implementation of fourier kernels

2013-02-27 Thread someone
I know that there is already some internal code to generalize the various integral transforms (take a look at sympy/integrals/transforms.py). I Long ago I wanted to make a general integral_transform function that would take one (or even two in the asymmetric case) kernels and the function

Re: [sympy] generating difference equations

2013-02-27 Thread Chris Smith
but for arbitrary order and also multivariate D. This is just something that's very error prone when done by hand. Exactly. I am thinking forward, backward, centered and arbitrary order. And for those donig finite element, similar tools could be made available. SymPy wouldn't solve the

[sympy] Failing tests

2013-02-27 Thread Manoj Kumar
Hello, Lets say I introduce a new feature and add tests. Suppose I add a new hint in the ODE module. Due to that , many of the previous tests also fail. Am I supposed to change every one of them before commiting? -- You received this message because you are subscribed to the Google Groups

Re: [sympy] Failing tests

2013-02-27 Thread Stefan Krastanov
Test should never fail in a pull request that is not WIP. Yes, you can modify them, if it is ok to change them, due to new functionality. However, it is much more probable that failing tests tell you that something is wrong with your code. For instance: Adding something to `simplify` that

[sympy] Groups module

2013-02-27 Thread Mary Clark
In addition to what Aaron said in this pull request (https://github.com/sympy/sympy/pull/1810) about redesigning how some of the group theory code works, what other things are still waiting to be implement/are wanted to be added? I personally think that most of the stuff about groups should be

Re: [sympy] Groups module

2013-02-27 Thread Aaron Meurer
On Feb 27, 2013, at 8:18 AM, Mary Clark mary.spritel...@gmail.com wrote: In addition to what Aaron said in this pull request ( https://github.com/sympy/sympy/pull/1810) about redesigning how some of the group theory code works, what other things are still waiting to be implement/are wanted to be

Re: [sympy] Groups module

2013-02-27 Thread David Joyner
On Wed, Feb 27, 2013 at 10:18 AM, Mary Clark mary.spritel...@gmail.com wrote: In addition to what Aaron said in this pull request (https://github.com/sympy/sympy/pull/1810) about redesigning how some of the group theory code works, what other things are still waiting to be implement/are wanted

Re: [sympy] crypto in sympy?

2013-02-27 Thread David Joyner
On Fri, Feb 22, 2013 at 8:35 PM, Aaron Meurer asmeu...@gmail.com wrote: On Fri, Feb 22, 2013 at 6:00 PM, David Joyner wdjoy...@gmail.com wrote: ... Tests and docstrings serve different purposes. Docstring examples should demonstrate to the user what the functionality is, and what the input

Re: [sympy] crypto in sympy?

2013-02-27 Thread Aaron Meurer
It means there is whitespace at the end of the line. Use bin/strip_whitespace to fix the problem. Aaron Meurer On Feb 27, 2013, at 10:11 AM, David Joyner wdjoy...@gmail.com wrote: On Fri, Feb 22, 2013 at 8:35 PM, Aaron Meurer asmeu...@gmail.com wrote: On Fri, Feb 22, 2013 at 6:00 PM, David

Re: [sympy] adding Mod to lambdify

2013-02-27 Thread G B
I'll give this a shot this weekend if I can. I haven't submitted a pull request before, but at some point I'd like to figure it out… Cheers— Greg On Feb 26, 2013, at 7:46 PM, Aaron Meurer asmeu...@gmail.com wrote: Great. If you could make a pull request with this change, that would be

Re: [sympy] adding Mod to lambdify

2013-02-27 Thread Aaron Meurer
Great. Let us know if you need any help. We help people with git problems all the time. Aaron Meurer On Feb 27, 2013, at 12:14 PM, G B g.c.b.at.w...@gmail.com wrote: I'll give this a shot this weekend if I can. I haven't submitted a pull request before, but at some point I'd like to figure

Re: [sympy] more Mod problems

2013-02-27 Thread Aaron Meurer
There's no good reason. It's just not implemented yet. Mod(Rational(5, 7), 1).n() works because the Mod already returns 5/7, so it's just the same as Rational(5, 7).n(). It looks like Mod doesn't implement evalf at all, and it doesn't work automatically (that only happens if the function name is

Re: [sympy] Re: Groups module

2013-02-27 Thread David Joyner
On Wed, Feb 27, 2013 at 2:36 PM, Mary Clark mary.spritel...@gmail.com wrote: David: Do you have anything specific that you think would be beneficial to be implemented? I think it would be nice to have the classical groups over finite fields implemented, as well as their representations as

Re: [sympy] more Mod problems

2013-02-27 Thread Chris Smith
It looks like Mod doesn't implement evalf at all, and it doesn't work automatically (that only happens if the function name is the same as the mpmath function name). It should be easy. Just evaluate the arguments, and then take the mod of them. In general this is not going to work: ```

Re: [sympy] crypto in sympy?

2013-02-27 Thread David Joyner
On Wed, Feb 27, 2013 at 12:29 PM, Aaron Meurer asmeu...@gmail.com wrote: It means there is whitespace at the end of the line. Use bin/strip_whitespace to fix the problem. Thank you! That did it. I guess sympy counts line numbers differently than I expected. I have a new question. This is

Re: [sympy] crypto in sympy?

2013-02-27 Thread Chris Smith
if bad boolean condition: raise ValueError(don't do that) I *think* the old style is raise ValueError, 'this' but the new style is as you have it above. -- You received this message because you are subscribed to the Google Groups sympy group. To unsubscribe from this group and stop

Re: [sympy] crypto in sympy?

2013-02-27 Thread David Joyner
On Wed, Feb 27, 2013 at 3:58 PM, Chris Smith smi...@gmail.com wrote: if bad boolean condition: raise ValueError(don't do that) I *think* the old style is raise ValueError, 'this' but the new style is as you have it above. Thanks Chris, I think you are right. With luck, I might be

Re: [sympy] more Mod problems

2013-02-27 Thread Aaron Meurer
On Wed, Feb 27, 2013 at 1:41 PM, Chris Smith smi...@gmail.com wrote: It looks like Mod doesn't implement evalf at all, and it doesn't work automatically (that only happens if the function name is the same as the mpmath function name). It should be easy. Just evaluate the arguments, and then

Re: [sympy] Re: Groups module

2013-02-27 Thread Aaron Meurer
On Wed, Feb 27, 2013 at 1:32 PM, David Joyner wdjoy...@gmail.com wrote: On Wed, Feb 27, 2013 at 2:36 PM, Mary Clark mary.spritel...@gmail.com wrote: David: Do you have anything specific that you think would be beneficial to be implemented? I think it would be nice to have the classical

Re: [sympy] more Mod problems

2013-02-27 Thread G B
I'm not sure it matters in the end, but it looks like Mod(Rational(15,7),1).n() works ok too. I think what's happening is that when pi isn't in the argument list, it basically gets simplified when the class construction calls Mod.eval but Mod.eval doesn't know how to simplify with pi. I've

Re: [sympy] more Mod problems

2013-02-27 Thread Aaron Meurer
On Wed, Feb 27, 2013 at 5:46 PM, G B g.c.b.at.w...@gmail.com wrote: I'm not sure it matters in the end, but it looks like Mod(Rational(15,7),1).n() works ok too. I think what's happening is that when pi isn't in the argument list, it basically gets simplified when the class construction calls

Re: [sympy] more Mod problems

2013-02-27 Thread G B
Why not just convert each arg to Float and use %, and leave the details up to Float.__mod__. In all honesty, because I have very little idea what I'm doing... =) I just tried this, but it failed: def _eval_evalf(self,prec): args=[Float(x,prec) for x in self.args] return N(args[0] %

Re: [sympy] Re: Implementation of fourier kernels

2013-02-27 Thread Amit Jamadagni
That would be great and I would like to work on it. Can you guide me how to start about it.I have already looked into the integral transforms module.Thank you. On Wed, Feb 27, 2013 at 4:13 PM, someone someb...@bluewin.ch wrote: I know that there is already some internal code to generalize the

Re: [sympy] Improved ODE Solver

2013-02-27 Thread Manoj Kumar
Aaron: Thanks for your feedback. I've seen the maple docs, and found out that they use lie groups and symmetry methods also to solve ODE's. It is not implemented in sympy. I've just started reading up on it. Do you think it would be a good idea to include it in my SOC proposal? On Wed, Feb 27,

Re: [sympy] more Mod problems

2013-02-27 Thread Chris Smith
Mod(1e-40,3) 0.0 1e-40 % 3 9.9993e-41 ``` Isn't that just a roundoff error. If you use Float, you get 1e-40. That is not the point here...in the first case, feeding floats to Mod results in an incorrect zero whereas feeding the same numbers to mod in the second results in the

Re: [sympy] Improved ODE Solver

2013-02-27 Thread Stefan Krastanov
I've seen the maple docs, and found out that they use lie groups and symmetry methods also to solve ODE's. It is not implemented in sympy. I've just started reading up on it. Do you think it would be a good idea to include it in my SOC proposal? If done well, such additional solvers (or

Re: [sympy] crypto in sympy?

2013-02-27 Thread David Joyner
On Wed, Feb 27, 2013 at 4:57 PM, David Joyner wdjoy...@gmail.com wrote: On Wed, Feb 27, 2013 at 3:58 PM, Chris Smith smi...@gmail.com wrote: if bad boolean condition: raise ValueError(don't do that) I *think* the old style is raise ValueError, 'this' but the new style is as you have

Re: [sympy] more Mod problems

2013-02-27 Thread G B
It looks like this works, and degrades more gracefully than the other methods I've shown when the arguments can't be reduced to Floats: def _eval_evalf(self,prec): args=[N(x,prec) for x in self.args] return N(args[0] % args[1],prec) On Wednesday, February 27, 2013 6:28:54