[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Inverse Laplace transform?
From: |
Joe Koski |
Subject: |
Re: Inverse Laplace transform? |
Date: |
Sun, 10 Dec 2006 13:25:18 -0700 |
User-agent: |
Microsoft-Entourage/11.2.5.060620 |
on 12/10/06 12:31 PM, Doug Stewart at address@hidden wrote:
> Joe Koski wrote:
>> on 12/10/06 10:36 AM, Doug Stewart at address@hidden wrote:
>>
>>
>>> Is there an inverse Laplace transform function in Octave?
>>> Doug Stewart
>>>
>>
>> Doug,
>>
>> Check ifft at http://octave.sourceforge.net/index/index.html, or help ifft
>> at the octave prompt.
>>
>> Joe
>>
>>
> Thanks Joe
> I did look there and there is nothing for Inverse Laplace transform that
> I can see.
>
>
> I have written up a crude version that is not ready for prime time yet.
> I thought I would ask before I spent the time to reinvent the wheel :-)
>
> What I have is a function ( for the controls tool box) that takes in a
> sys type transfer function.
> It then uses the residue function to do the partial fraction
> expansion.From this I form up a string that is the time representation
> of each factor. What I am having a little difficulty with is how to
> get the string formatted nicely.
>
> I have a cell array with each location holding a string that is the time
> representation of a term.
> What I want to do is take these and form them into one long string
> that has all the "+"'s and "-"'s between each term properly formated.
>
> So any help would be appreciated.
>
> resultstring = cell(1,1) "+" cell(2,1) "-" cell(3,1)
>
> is what I can't seem to do?
>
> Thanks in advance for any help.
>
> Doug Stewart
>
Doug,
Sorry, I was reading Fourier instead of Laplace transform. I guess I was
just seeing the word transform. For calculation of inverse Laplace
transforms, I use Maxima, a symbolic math package, and it works well.
Sorry for the confusion.
Joe