Thread Subject: plotting complex numbers

Hello,

I have MATLAB which I have used very successfully for other stuff. I have never used it for complex numbers. A colleague wishes to plot a function - he is having problems with another program and asked me about Matlab ;-)

The funtion is

1 + 1/(x(iy-x))

for -2 < x < 2
    -2 < y < 2

I am guessing I need to plot an array of complex numbers or something

Can some kind soul please tell me how to do this? I would rather not have to do a refresher course on complex numbers ;-)

"Jason" <j_henderson44@REMOVEhotmail.com> wrote in message <ghbfm4$bfh$1@fred.mathworks.com>...
> Hello,
>
> I have MATLAB which I have used very successfully for other stuff. I have never used it for complex numbers. A colleague wishes to plot a function - he is having problems with another program and asked me about Matlab ;-)
>
> The funtion is
>
> 1 + 1/(x(iy-x))
>
> for -2 < x < 2
> -2 < y < 2
>
> I am guessing I need to plot an array of complex numbers or something
>
> Can some kind soul please tell me how to do this? I would rather not have to do a refresher course on complex numbers ;-)

you can just plot imaginary numbers

x = -2: 0.01: 2;
[X Y] = meshgrid(x);
Z = 1+1./(X .* (1i*Y-X));

plot(Z, '.-')

do you want to plot it vs x and y? In signal processing you would do magnitude and phase plots
mesh(X, Y, log10(abs(Z)))

mesh(X, Y, unwrap(angle(Z)))

If this doesn't help you may need to explain more.
~Adam