I want to import a .raw file into MATLAB as a matrix (frames x spatial x spectral). Is there a built-in function to do this?
You can also read the file directly. But you'll need to convert it to DNG first. See this: http://blogs.mathworks.com/steve/2011/03/08/tips-for-reading-a-camera-raw-file-into-matlab/
If you're referring to a raw image file from a camera, I would check out the submission RAW Camera File Reader from Bryan White on the MathWorks File Exchange.