[sympy] Re: Handling derivatives while evaluating the Inverse Laplace Transform of Functions

2013-09-26 Thread Saurabh Jha
Hi Harsh, Please have a look at our Development Workflow page[1] to get started. If you have already gone through this, submit a pull request so that we can review it and check it in. Start small and just push your preliminary ideas first so that we can discuss and refine it. -Saurabh [1] htt

[sympy] Re: Handling derivatives while evaluating the Inverse Laplace Transform of Functions

2013-09-26 Thread Harsh Gupta
Hi, Sympy is directly using inverse Millen formula Integral(exp(s*t)*F, (s, c - I*oo, c + I*oo)) to evaluate the inverse_laplace_transform function. But it is not working well with some functions which can be easily evaluated by hand. For example 1. A NotImplementedError is raised when I tr

Re: [sympy] Re: Handling derivatives while evaluating the Inverse Laplace Transform of Functions

2013-09-26 Thread Aaron Meurer
The solution to this is to call apart on the arguments. For instance In [9]: apart(2/(s**2*(s**2 + 1))) Out[9]: 2 2 - ── + ── 22 s + 1 s In [10]: inverse_laplace_transform(-2/(s**2 + 1), s, t) Out[10]: -2⋅sin(t)⋅Heaviside(t) In [11]: inverse_laplace_transform(2/s**2,

Re: [sympy] Re: Handling derivatives while evaluating the Inverse Laplace Transform of Functions

2013-09-28 Thread Harsh Gupta
I changed the inverse_laplace_transform function in sympy.integrals.transforms to first break the given function in partial fractions and calculate the inverse_laplace_transform as the sum of inverse_laplace_transform of the partial fractions. def inverse_laplace_transform(F, s, t, plane=None,

Re: [sympy] Re: Handling derivatives while evaluating the Inverse Laplace Transform of Functions

2013-09-28 Thread Aaron Meurer
On Sat, Sep 28, 2013 at 9:51 AM, Harsh Gupta wrote: > I changed the inverse_laplace_transform function in > sympy.integrals.transforms to first break the given function in partial > fractions and calculate the inverse_laplace_transform as the sum of > inverse_laplace_transform of the partial fract

Re: [sympy] Re: Handling derivatives while evaluating the Inverse Laplace Transform of Functions

2013-10-01 Thread Harsh Gupta
Sorry for a late reply. Though equivocally breaking the function into partial fraction can lead to bad results, applying partial fraction gives let us solve the inverse_laplace_transforms which are not solvable now. So, I think as of now we should go ahead with equivocally breaking the function in

Re: [sympy] Re: Handling derivatives while evaluating the Inverse Laplace Transform of Functions

2013-10-01 Thread Aaron Meurer
The partial fraction decomposition can be done completely separately in the integral transformation code. It doesn't have to happen in integrate() at this point. Aaron Meurer On Tue, Oct 1, 2013 at 11:52 AM, Harsh Gupta wrote: > Sorry for a late reply. > Though equivocally breaking the function