Library
Module
Module type
Parameter
Class
Class type
Precision independent signature for FFTW3 submodules.
Precision
val float : (float, float_elt) Bigarray.kind
Float of the precision of this module. Use this to create precision independent code.
val complex : (Complex.t, complex_elt) Bigarray.kind
Complex of the precision of this module. Use this to create precision independent code.
Specifying plans
type measure =
| Estimate
(*No measurements are made, use a simple heuristic to pick a (probably sub-optimal) plan quickly.
*)| Measure
(*Find an optimized plan by actually computing several FFTs and measuring their execution time.
*)| Patient
(*Like
*)Measure
, but considers a wider range of algorithms and often produces a "more optimal" plan at the expense of several times longer planning time.| Exhaustive
(*Like
*)Patient
, but considers an even wider range of algorithms, including many that are thought unlikely to be fast, to produce the most optimal plan but with a substantially increased planning time.
Planning-rigor flags.
type r2r_kind =
| R2HC
(*real to halfcomplex
*)| HC2R
(*halfcomplex to real
*)| DHT
(*discrete Hartley Transform
*)| REDFT00
(*real-even DFT: even around j=0 and even around j=n-1
*)| REDFT01
(*real-even DFT: even around j=0 and odd around j=n
*)| REDFT10
(*real-even DFT: even around j=-0.5 and even around j=n-0.5
*)| REDFT11
(*real-even DFT: even around j=-0.5 and odd around j=n-0.5
*)| RODFT00
(*real-odd DFT; odd around j=-1 and odd around j=n
*)| RODFT01
(*real-odd DFT; odd around j=-1 and even around j=n-1
*)| RODFT10
(*real-odd DFT; odd around j=-0.5 and odd around j=n-0.5
*)| RODFT11
(*real-odd DFT; odd around j=-0.5 and even around j=n-0.5
*)
Real-to-Real transform kinds. The real-even (resp. real-odd) DFT are somtimes called Discrete Cosine Transform (DCT) (resp. Discrete Sine Transform (DST)). Note that the explanations of the various transforms are for an input array of dimension n
and C layout (i.e. the input array is input[0..n-1]
). The logical size N
is N=2(n-1)
for REDFT00
, N=2(n+1)
for RODFT00
, and N=2n
otherwise. See the FFTW manual for more details.
Executing plans
val exec : 'a plan -> unit
exec plan
executes the plan
on the arrays given at the creation of this plan. This is the normal way to execute any kind of plan.
This function is thread safe (and may run the actual computation on a different core than the main program).
module Guru : sig ... end
Guru execution of plans.
Creating plans
module Genarray : sig ... end
FFT of Bigarray.Genarray.
module Array1 : sig ... end
FFT of Bigarray.Array1.
module Array2 : sig ... end
FFT of Bigarray.Array2.
module Array3 : sig ... end
FFT of Bigarray.Array3.