what does this function does?

Here zfSig is a function. The code is:

zfSig=remTrend(zfSig,winLength);

[José-Luis]

From its name, I would guess it removes trends. Now seriously. How do you expect us to know what a function does just by looking at its name? All I can tell you is that it is not a Matlab built-in function. To know what it does you need to look at the source code. Barring that, you could ask the author of the function. Another, less efficient alternative, is to run it and try to guess what it does.

[KJDS SRINIVASA RAO]

Thanks man