# Calculate power spectrum?

1. May 21, 2012

### goldtree

Hello!

I am doing a thesis in ecology using a two dimensional binary cellular automata. I have sampled a parameter for a number of generations and I would like to calculate the power spectrum for this data. I had been planning to use a software for this, but now it seems I have to do it manually.

Does anyone know or have any helpful links to how this can be done?

Grateful for any help,
Jimmy

2. May 22, 2012

### Jano L.

What kind of function do you have to find spectrum of?

In physics (acoustics, optics), the power spectrum of function $f(t)$ is sometimes called to be the function

$$I(\omega) = \tilde f(\omega)^* \tilde f (\omega) ,$$

measuring the strength of vibrations at frequency $\omega$.

The function $\tilde f (\omega)$ is the Fourier component of the function f(t) on the time interval 0..T considered:

$$\tilde f(\omega) = \frac{1}{T}\int_0^T f(t) e^{-i \omega t} dt.$$

3. May 23, 2012

### goldtree

It's a power law function. I found this site that I think will help me:

tuvalu.santafe.edu/~aaronc/powerlaws/

Thanks though for trying to help!