# DerivativeFilter[] is scaling down the data by ~100 or so, not a true differentiation? [duplicate]

I'm running the following function

 vzz = DerivativeFilter[z["Path"][[All, 2]], {1}];


But if I then integrate vzz the output z is about 100 smaller than the original z.

Why is this so? I thought DerivativeFilter would provide an alternative to a finite difference scheme but the magnitude of the output is just wrong.

## marked as duplicate by MarcoB, user9660, b.gates.you.know.what, Bob Hanlon, JensFeb 15 '16 at 7:10

• Try DerivativeFilter[{{a, b}, {c, d}}, {1}] – Dr. belisarius Feb 10 '16 at 21:19