How to compute derivatives of discrete complex data?

Hello:

I need to compute derivatives of complex discrete data in Matlab, anyone here can tell me how to perform it? (Build-in functions?)

For example, I have the following frequency dependent data:

f X
f1 x1-jy1
f2 x2+jy2
f3 x3-jy3
...
....

Where fi,xi and yi are real numbers with particular value. How should I compute

f*dx/df in matlab?

Thanks in advance.