`fftw`

Gets or sets how the FFT planner optimizes its algorithm.

Category: Mathematics > Fourier Analysis and Filtering

Syntax

method = fftw('planner')

Returns the current planner method name.

fftw('planner', method)

Sets the planner method, for example 'estimate' or 'measure'.

Description

In MATLAB, fftw tunes the FFTW library behind fft and its relatives. Slower planners such as 'measure' try several algorithms for a given size and can speed up repeated transforms of that size.

The setting never changes the numerical result, only the speed. It is kept so that code written for MATLAB runs unchanged.

Input arguments

'planner': Selects the planner setting.
method: Planner method name. 'estimate' is the default and picks a plan with a heuristic.

Output arguments

method: Character vector with the current planner method.

Example

Read the planner

fftw('planner')

Output

ans = 'estimate'

Notes

In MatLivre only the 'planner' query and assignment are meaningful. The transforms do not depend on the setting.

fftw