[PD] derivative?

[Oded Ben-Tal]

Does anyone know of a patch/object that calculates the derivative of an 
incoming sequence of messages (not signal)?
I am trying to figure out a way of calculating the derivative (by DPCM) 
but all I can come up with are very cumbersome and ugly (keeping the last 
4 values and then switching their positions ready for the next iteration 
works in c, but seems awkward in pd) I presume there is a simple elegant 
way of doing it but I just can't see it.

Thanks
Oded

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___________________________________________________
Oded Ben-Tal
http://ccrma.stanford.edu/~oded
oded at ccrma.stanford.edu