LMU/musrfit
5
0
Fork 0
Code Issues 6 Pull Requests Actions Packages Projects Releases 4 Activity

proper phase correction for Re/Im Fourier transform (MUSR-206)

Browse Source
This commit is contained in:
suter_a
2011-11-14 20:24:27 +00:00
parent a41c518ecc
commit a63ed33de7
2 changed files with 12 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
ChangeLog
View File

@ -17,6 +17,7 @@ NEW the chi^2 calculation in single-histogram and asymmetry fits is parallelized
if musrfit is built using a compiler supporting OpenMP (e.g. GCC >= 4.2) if musrfit is built using a compiler supporting OpenMP (e.g. GCC >= 4.2)
Using --disable-omp this feature can be disabled on the configure level. Using --disable-omp this feature can be disabled on the configure level.
NEW any2many: force the user to define the exact NeXus ouput format (HDF4,HDF5,XML) NEW any2many: force the user to define the exact NeXus ouput format (HDF4,HDF5,XML)
FIXED proper phase correction for Re/Im Fourier transform (MUSR-206)
FIXED when release or restore is called (command block commands), the FIXED when release or restore is called (command block commands), the
corresponding parameter error is set to 2% of its parameter value (MUSR-188). corresponding parameter error is set to 2% of its parameter value (MUSR-188).
FIXED the wrong normalization when using "SCALE_N0_BKG FALSE" together with view_packing (MUSR-184) FIXED the wrong normalization when using "SCALE_N0_BKG FALSE" together with view_packing (MUSR-184)

12
src/classes/PFourier.cpp
View File

@ -36,6 +36,7 @@ using namespace std;
#include "TH1F.h" #include "TH1F.h"
#include "TF1.h" #include "TF1.h"
#include "TAxis.h"
//#include "TFile.h" //#include "TFile.h"
@ -179,9 +180,18 @@ void PFourier::Transform(UInt_t apodizationTag)
fftw_execute(fFFTwPlan); fftw_execute(fFFTwPlan);
// correct the phase for tstart != 0.0 // correct the phase for tstart != 0.0
// find the first bin >= fStartTime
Double_t shiftTime = 0.0;
for (Int_t i=1; i<fData->GetXaxis()->GetNbins(); i++) {
if (fData->GetXaxis()->GetBinCenter(i) >= fStartTime) {
shiftTime = fData->GetXaxis()->GetBinCenter(i);
break;
}
}
Double_t phase, re, im; Double_t phase, re, im;
for (UInt_t i=0; i<fNoOfBins; i++) { for (UInt_t i=0; i<fNoOfBins; i++) {
phase = 2.0*PI/(fTimeResolution*fNoOfBins) * i * fStartTime; phase = 2.0*PI/(fTimeResolution*fNoOfBins) * i * shiftTime;
re = fOut[i][0] * cos(phase) + fOut[i][1] * sin(phase); re = fOut[i][0] * cos(phase) + fOut[i][1] * sin(phase);
im = -fOut[i][0] * sin(phase) + fOut[i][1] * cos(phase); im = -fOut[i][0] * sin(phase) + fOut[i][1] * cos(phase);
fOut[i][0] = re; fOut[i][0] = re;