No BSD License  

Highlights from
Figure out residue of a function of complex variable

Be the first to rate this file! 1 Download (last 30 days) File Size: 3.12 KB File ID: #12842

Figure out residue of a function of complex variable

by Pu Ke

 

01 Nov 2006 (Updated 06 Nov 2006)

Try to figure out all residues of corresponding singular point

| Watch this File

File Information
Description

This M-file try to figure out all singular point and corresponding residues when you enter a function of complex variables which the number of its singular point is finite, and specified variable(like z),example:res=myrese('1/(z*(z+1)),z').If failed, the program will return all singular point,like: res=myrese('1/(z^5-1),z').
  If the number of singular point is infinite and there is a series can describe all of its singular points, then it will return the series and ask user to choose one singular point at the line of the series for calculus of residue, like res=myrese('cot(z),z').
  If there is no singular point in finite region,the error message will prompt out,like:res=myrese('cos(z),z').
  It can also compute the residue of a specific singular point with a additional argument like:res=myrese('1/z,z','0').
   For I am a sophermore whose major is physics, I found that in most time we use residue to calculate the real integral,the key step is find which residue is in the region of integral path(esp in a Argument range).To set return values in a matrix with two rows which the first are singular points the second are corresponding residues is relatively clear to use. But I still can't work out a way to find the residues exactly in the region I want, that needs symbolic inequality what MATLAB can't do.Because the intensive study,I don't think I have more time to work on this file.But I hope someone can develop this file so that it can do a lot of cool things like calculate some specific integral, inverse Laplace transform etc. Thank you!
   Finally, I must mention that all of the input must in a character format. In another word all the argument must in single quotation mark.

Required Products Symbolic Math Toolbox
MATLAB release MATLAB 7.2 (R2006a)
Tags for This File  
Everyone's Tags
Tags I've Applied
Add New Tags Please login to tag files.
Please login to add a comment or rating.
Updates
02 Nov 2006

There are some mistakes in description and messages.

06 Nov 2006

Character format is useless, so I change the return values in a matrix with two rows: the first is singular points, the second is corresponding residues.It's more clearer than the last version.

Tag Activity for this File
Tag Applied By Date/Time
symbolic math Pu Ke 22 Oct 2008 08:46:41
residue Pu Ke 22 Oct 2008 08:46:41
function Pu Ke 22 Oct 2008 08:46:41
singular Pu Ke 22 Oct 2008 08:46:41
point Pu Ke 22 Oct 2008 08:46:41
complex Pu Ke 22 Oct 2008 08:46:41

Contact us at files@mathworks.com