# derivfrac3D.m

E. Koenig, 08/04/2010

Pseudo-fractional derivation of a 3D field.

This operation is seen as the inverse of the pseudo-fractional integration. It preserves the scale invariance of the initial 3D field. It is realized by a high-pass filter in k^H in the Fourier domain.

The initial field is scale invariant and characterized by

The pseudo-fractional derivation will create a rougher, more intermittent version of the initial field. This new field is scale invariant and characterized by

## Contents

- Use
- Inputs
- Outputs

## Use

y = derivfrac3D(x, H, S, zero);

## Inputs

- x: input 3D field
- H: parameter of the high-pass filter
- S: size of the initial filed
- zero: 1 - management of k=0, 0 - else (default)

## Outputs

- y: derived 3D field.