Psychoacoustic Masking Curve I am trying to implement a Weighted Matching Pursuit algorithm. Essentially I would like to weight the atoms of a Dictionary (redundant matrix) with a frequency masking function, like the one specified for MP3. I have read some of the papers, and theory of frequency masking, but I am still having trouble figuring out how to generate the function in Matlab. My dictionary contains frequencies ranging from -fs/2 to fs/2. fs = sampling frequency.

If anyone can help me out with a quick way to generate this kind of function I would be most grateful.
Psycho acoustic masking is a VERY complicated subject. The masking thresholds (energy required to have one sound be audible in the presence of another) is a very complex function of 


Spectral content and overlap
Spatial presentation (there are many books just on binaural masking alone)
Time shapes of the waveforms
Time alignment and envelopes of the wave forms


Even the more advanced audio codecs (such HE AAC) use very simplified models because a more accurate one is very complicated. 

The best choice really depends on your application and requirements, monoaural masking of simultaneous sinusoids is probably the easiest case. You may find some helpful stuff here https://engineering.purdue.edu/~malcolm/interval/1998-010/