From 23af7e435a4acb100add288dd5322697cb9b5a0a Mon Sep 17 00:00:00 2001
From: Andrew Heather <a.heather@opencfd.co.uk>
Date: Fri, 29 Dec 2017 23:57:22 +0000
Subject: [PATCH] ENH: FFT - removed power-of-2 constraint on number of samples
---
.../utilities/postProcessing/noise/noise.C | 3 +--
.../utilities/postProcessing/noise/noiseDict | 6 ++----
src/randomProcesses/fft/fft.C | 14 --------------
.../noise/noiseModels/noiseModel/noiseModel.C | 10 ----------
.../noise/noiseModels/noiseModel/noiseModel.H | 3 ---
.../noise/noiseModels/pointNoise/pointNoise.H | 3 +--
.../noise/noiseModels/surfaceNoise/surfaceNoise.H | 3 +--
.../LES/vortexShed/system/noiseDict-point | 2 +-
.../LES/vortexShed/system/noiseDict-surface | 2 +-
9 files changed, 7 insertions(+), 39 deletions(-)
diff --git a/applications/utilities/postProcessing/noise/noise.C b/applications/utilities/postProcessing/noise/noise.C
index 97f2cb775f3..61653947eaa 100644
--- a/applications/utilities/postProcessing/noise/noise.C
+++ b/applications/utilities/postProcessing/noise/noise.C
@@ -74,8 +74,7 @@ Usage
}
}
- // Number of samples in sampling window
- // Must be a power of 2, default = 2^16 (=65536)
+ // Number of samples in sampling window, default = 2^16 (=65536)
N 4096;
// Write interval for FFT data, default = 1
diff --git a/applications/utilities/postProcessing/noise/noiseDict b/applications/utilities/postProcessing/noise/noiseDict
index ca808462c4c..9323c98df62 100644
--- a/applications/utilities/postProcessing/noise/noiseDict
+++ b/applications/utilities/postProcessing/noise/noiseDict
@@ -72,8 +72,7 @@ surfaceNoiseCoeffs
// Reference density (to convert from kinematic to static pressure)
rhoRef 1.205;
- // Number of samples in sampling window
- // Must be a power of 2, default = 2^16 (=65536)
+ // Number of samples in sampling window, default = 2^16 (=65536)
N 4096; // 8192; // 4096;
// Lower frequency limit, default = 25Hz
@@ -123,8 +122,7 @@ pointNoiseCoeffs
// Reference density (to convert from kinematic to static pressure)
rhoRef 1.2;
- // Number of samples in sampling window
- // Must be a power of 2, default = 2^16 (=65536)
+ // Number of samples in sampling window, default = 2^16 (=65536)
N 4096;
// Lower frequency limit, default = 25Hz
diff --git a/src/randomProcesses/fft/fft.C b/src/randomProcesses/fft/fft.C
index 658e477f1e2..260bc1901e0 100644
--- a/src/randomProcesses/fft/fft.C
+++ b/src/randomProcesses/fft/fft.C
@@ -95,20 +95,6 @@ void Foam::fft::transform
transformDirection dir
)
{
- forAll(nn, idim)
- {
- // Check for power of two
- unsigned int dimCount = nn[idim];
- if (!dimCount || (dimCount & (dimCount - 1)))
- {
- FatalErrorInFunction
- << "number of elements in direction " << idim
- << " is not a power of 2" << endl
- << " Number of elements in each direction = " << nn
- << abort(FatalError);
- }
- }
-
// Copy field into fftw containers
const label N = field.size();
fftw_complex in[N], out[N];
diff --git a/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.C b/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.C
index 84ba84ca4be..008d161cbd9 100644
--- a/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.C
+++ b/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.C
@@ -206,16 +206,6 @@ bool Foam::noiseModel::read(const dictionary& dict)
dict.readIfPresent("maxPressure", maxPressure_);
dict.readIfPresent("outputPrefix", outputPrefix_);
- // Check number of samples - must be a power of 2 for our FFT
- bool powerOf2 = ((nSamples_ != 0) && !(nSamples_ & (nSamples_ - 1)));
- if (!powerOf2)
- {
- FatalIOErrorInFunction(dict)
- << "N: Number of samples in sampling windows must be a "
- << "power of 2"
- << exit(FatalIOError);
- }
-
if (fLower_ < 0)
{
FatalIOErrorInFunction(dict)
diff --git a/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.H b/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.H
index b74e053dd00..336f46ca863 100644
--- a/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.H
+++ b/src/randomProcesses/noise/noiseModels/noiseModel/noiseModel.H
@@ -66,9 +66,6 @@ Description
writeOctaves | Write octaves data | no | yes
\endtable
-Note
- The number of samples in the sampling window must be a power of 2
-
SourceFiles
noiseModel.C
diff --git a/src/randomProcesses/noise/noiseModels/pointNoise/pointNoise.H b/src/randomProcesses/noise/noiseModels/pointNoise/pointNoise.H
index 3e05e14cb7d..1a860fe8e2c 100644
--- a/src/randomProcesses/noise/noiseModels/pointNoise/pointNoise.H
+++ b/src/randomProcesses/noise/noiseModels/pointNoise/pointNoise.H
@@ -33,8 +33,7 @@ Description
// Pressure reference
pRef 0;
- // Number of samples in sampling window
- // Must be a power of 2, default = 2^16 (=65536)
+ // Number of samples in sampling window, default = 2^16 (=65536)
N 4096;
// Lower frequency bounds
diff --git a/src/randomProcesses/noise/noiseModels/surfaceNoise/surfaceNoise.H b/src/randomProcesses/noise/noiseModels/surfaceNoise/surfaceNoise.H
index ad7cedebcc0..6cb08327ea5 100644
--- a/src/randomProcesses/noise/noiseModels/surfaceNoise/surfaceNoise.H
+++ b/src/randomProcesses/noise/noiseModels/surfaceNoise/surfaceNoise.H
@@ -33,8 +33,7 @@ Description
// Pressure reference
pRef 0;
- // Number of samples in sampling window
- // Must be a power of 2, default = 2^16 (=65536)
+ // Number of samples in sampling window, default = 2^16 (=65536)
N 4096;
// Lower frequency bounds
diff --git a/tutorials/incompressible/pimpleFoam/LES/vortexShed/system/noiseDict-point b/tutorials/incompressible/pimpleFoam/LES/vortexShed/system/noiseDict-point
index 2f640c98c26..b7935e68103 100644
--- a/tutorials/incompressible/pimpleFoam/LES/vortexShed/system/noiseDict-point
+++ b/tutorials/incompressible/pimpleFoam/LES/vortexShed/system/noiseDict-point
@@ -45,7 +45,7 @@ pointNoiseCoeffs
separator " ";
// Number of samples in sampling window
- // Must be a power of 2, default = 2^16 (=65536)
+ // default = 2^16 (=65536)
N 4096;
rhoRef 1.205;
diff --git a/tutorials/incompressible/pimpleFoam/LES/vortexShed/system/noiseDict-surface b/tutorials/incompressible/pimpleFoam/LES/vortexShed/system/noiseDict-surface
index a1206332108..6d620735bc4 100644
--- a/tutorials/incompressible/pimpleFoam/LES/vortexShed/system/noiseDict-surface
+++ b/tutorials/incompressible/pimpleFoam/LES/vortexShed/system/noiseDict-surface
@@ -56,7 +56,7 @@ surfaceNoiseCoeffs
p Curle;
// Number of samples in sampling window
- // Must be a power of 2, default = 2^16 (=65536)
+ // default = 2^16 (=65536)
N 1024;
rhoRef 1.205;
--
GitLab