If you're looking for a simple import and speed isn't a concern you should try:
uiimport
A speedier load than this can be achieved using low-level IO functions.
Depending on your field, converting wavelength to wavenumber is achieved using either
waveNumber = 1./waveLength
%or
waveNumber = 2*pi./waveLength
The interpolation you are looking for can be achieved using either
interp1
%or
interp2
depending on the dimensions of your data, or using the
resample function if you want some antialiasing.
The FFT is done with the aptly named
fft
function.
I am not exactly sure what you're doing, but I think you could probably skip most of these steps and just fft the intensity vs wavelength data to achieve the same goal.
