[sympy] Re: GSoC Acceptance

I will dedicate this first week's blogpost (codesachin.blogspot.in) to a written solution (on paper) of the generic problem posted by Stefan. By the end of my GSoC period, I hope to enable my proposed module to solve problems of such type entirely in code. Hence, having the API in mind would be a g

Re: [sympy] Converting String to Sympy

In the end, the answer is "use evaluate=False with the addends: >>> Add(2,3,x,2*x,evaluate=False) x + 2*x + 2 + 3 If you must use a string then this it is as complicated as identifying the addends in the string. If you only use "+" to separate addends then >>> Add(*[S(a) for a in "2+3 + x + 2*x"

[sympy] Re: GSoC Acceptance

I think Stefan has already covered many good points here. I would request that in addition to the mock sympy sessions, you also write out (by hand or using something like LaTeX) the problems and make them available on the same wiki page. I find it helpful to see the notations people are working wi

[sympy] Converting String to Sympy

Hii, I want to convert "2+4 + 45+ 2*x + x + x**2" string into sympy object without AutoSimplification. I used both sympify and kernS. But they automatically simplifies and returns "3*x + x**2 + 51" How to convert the string into sympy object without simplification. Thanks, Abhishek -- You rec

[sympy] Re: GSoC Acceptance

I'm a little hashed for time, so it would be great for you students to actually send a pull request to https://github.com/sympy/planet.sympy.org with your blog (edit planet.ini). Regarding your blogs, I don't want to stifle your creativity, but it would help me a lot if you have your name prominen

Re: [sympy] CoercionFailed error when trying to evaluate integral analytically

Do you know what the right answer should be? It gives 0 in Mateusz's new-polys branch. Aaron Meurer On Tue, May 28, 2013 at 11:30 AM, Will Furnass wrote: > Thanks Aaron. My code now looks as follows (T is now a lambda function and > the integral is evaluated over t=0..oo): > > ... > T = lambda

Re: [sympy] Functional equations

I guess a recurrence relation is a special case of a functional equation. I didn't consider that a functional equation might be transformable to a recurrence relation via a change of variable. I'm not sure how well your way works. If you take the classical functional equation f(a + b) = f(a)*f(b

Re: [sympy] Functional equations

If the functional equation contains f(a) and f(b), it can be reduced to a recurrence formula by k (x + 1) = a k x = b which is k = a - b x = b / (a - b) now the new function g(x) = f(k*x) displays the same equation as a recurrence equation [ g(x) = f(b), g(x+1) = f(a) ]. That was just an att

[sympy] Re: GSoC Acceptance

@Prasoon, I may pen some things down on a wiki page, I will point you to it. Do make the changes and comment as you see fit. On Tue, May 28, 2013 at 10:09 PM, Prasoon Shukla wrote: > Here's mine. I just created it today. > http://allpython.wordpress.com/ >

[sympy] Re: GSoC Acceptance

Here's mine. I just created it today. http://allpython.wordpress.com/ And I here's the link to the RSS feed: http://allpython.wordpress.com/feed/ Also, I am under some heavy load till this week ends due to a project. So, I might not be able to create the wi

Re: [sympy] CoercionFailed error when trying to evaluate integral analytically

Thanks Aaron. My code now looks as follows (T is now a lambda function and the integral is evaluated over t=0..oo): ... T = lambda t: Piecewise((0, t < 0), (k * D * pi * dx * expr8 / Q, t >= 0)) curve_expr = integrate(T(t - (x/V)), (x, 0, L)) vals = { P : 0.00022, k : 0.5, tau_s : 0

[sympy] Re: GSoC Acceptance

@Aaron, this is the link to my blog - http://codesachin.blogspot.in/ I am not that acquainted with RSS and feeds, but is this what you need? - http://codesachin.blogspot.in/feeds/posts/default On Tue, May 28, 2013 at 7:30 PM, Aaron Meurer wrote: > On May 28, 2013, at 5:30 AM, Stefan Krastanov

Re: [sympy] CoercionFailed error when trying to evaluate integral analytically

Are you sure you're using the git head? The T(t - (x/V)) in the integral is not allowed (we stopped making SymPy objects arbitrarily callable). I'm not sure if you meant for that to be a substitution or a multiplication, so I didn't try it further. Chances are it's fixed in https://github.com/sym

[sympy] CoercionFailed error when trying to evaluate integral analytically

Hi, I'm fairly new to sympy. I'm trying to evalute an integral analytically over the range 0..oo but when I run the last line in the script below I get the following error (using the sympy git head). CoercionFailed: can't convert DMP([[1], []], ZZ, ZZ[_a1,_b1]) of type from ZZ[_a1,_b1] to R

[sympy] Re: GSoC Acceptance

On May 28, 2013, at 5:30 AM, Stefan Krastanov wrote: Oh, one more thing. About actually representing your objects. Sympy roughly follows the following requirement `type(obj)(*obj.args)==obj`. It is rather important detail. Check out this https://github.com/sympy/sympy/wiki/Args-Invariant and ple

[sympy] Re: GSoC Acceptance

Hi Sachin. Yes, the one thing I need from you is your blog RSS feed. Send it to me, or send a pull request to https://github.com/sympy/planet.sympy.org (edit the planet.ini file). The same goes to the other accepted GSoC students. The reason we decided to have Gilbert and Stefan both comentor you

[sympy] Re: GSoC Acceptance

Oh, one more thing. About actually representing your objects. Sympy roughly follows the following requirement `type(obj)(*obj.args)==obj`. It is rather important detail. Check out this https://github.com/sympy/sympy/wiki/Args-Invariant and please learn why this invariant is important (tree travers

[sympy] Re: GSoC Acceptance

Hi Sachin and Prasoon, I have also CCed Aaron, Gilbert and the mailing list as a whole. If you have questions send them publicly to the mailing list, not privately to the mentors (unless you consider the issue to really be a private matter) First of all, congratulations! Be sure to setup blogs f

Re: [sympy] Re: Google Summer of Code Students Announced

Hi Isuru, I am sorry that the project was not accepted, but the reasons are not what you suggested. We received a lot of good applications and had to choose those that would be of greatest benefit for SymPy. Moreover, the projects that were accepted were those written in most details and showing g

[sympy] Re: Google Summer of Code Students Announced

I don't see the project idea "Mobile app for iOS and/or Android" in the list. I believe the reason is there is no mentor for that project. Isn't that unfair for the students who applied for that idea? On Tuesday, May 28, 2013 1:08:05 AM UTC+5:30, Aaron Meurer wrote: > > Hi everyone. As many o