///////////////////////////////////////////////////////////////////
//////// Go4 GUI example script fft.C
// J.Adamczewski, gsi, 30 May 2012
// NOTE: to be run in Go4 GUI local command line only!
// NEVER call this script in remote analysis process!!!
/////// Functionality:
// perfroms fft on histogram of name1 using the option as explained in root TVirtualFFT:FFT
/////// Usage:
// The draw flag switches if the results are displayed each time this macro is called
// if display is switched off, the result histogram is just updated in browser and existing displays
///////
Bool_t fft(const char* name1, Option_t* opt = "R2C M", Bool_t draw=kTRUE)
{
if(TGo4AbstractInterface::Instance()==0 || go4!=TGo4AbstractInterface::Instance()) {
std::cout <<"FATAL: Go4 gui macro executed outside Go4 GUI!! returning." << std::endl;
return kFALSE;
}
TString newname;
TString fullname1 = go4->FindItem(name1);
TObject* ob1 = go4->GetObject(fullname1,1000); // 1000=timeout to get object from analysis in ms
if ((ob1==0) || !ob1->InheritsFrom("TH1")) {
std::cout <<"fft could not get histogram "<<fullname1 << std::endl;
return kFALSE;
}
if(ob1->InheritsFrom("TH2") || ob1->InheritsFrom("TH3")){ // 2d
std::cout <<"fft does not support 2d/3d histogram "<<fullname1 << std::endl;
return kFALSE;
}
TH1* his1=(TH1*)ob1;
TString n1=his1->GetName();
TString t1=his1->GetTitle();
newname.Form("_fft_%s",opt);
TString finalname = n1+newname;
TString finaltitle = t1+newname;
// do fft here:
Int_t N = his1->GetNbinsX();
TH1D* result = new TH1D(finalname, finaltitle,N,0,N);
result->SetName(finalname);
result->SetTitle(finaltitle);
result->Reset("");
Double_t *in = new Double_t[N];
// since we do not know type of input histo, we copy contents to Double array:
for(Int_t ix=0; ix<N;++ix)
{
in[ix]=his1->GetBinContent(ix+1);
}
TVirtualFFT *thefft = TVirtualFFT::FFT(1, &N, opt);
thefft->SetPoints(in);
thefft->Transform();
Double_t re, im;
for (Int_t i=0; i<N; i++) {
thefft->GetPointComplex(i, re, im);
result->SetBinContent(i+1,TMath::Sqrt(re*re + im*im));
}
result->SetDirectory(0);
TString rname = go4->SaveToMemory("FFT", result, kTRUE);
std::cout<< "Saved result histogram to " << rname.Data() <<std::endl;
if(draw){
ViewPanelHandle vpanel = go4->StartViewPanel();
go4->DrawItem(rname, vpanel);
}
return kTRUE;
}
void PlotVectorPotential( const TString &sim, Int_t timestep, const TString &options="") {
#ifdef __CINT__
gSystem->Load("libptools.so");
#endif
PData *pData = PData::Get(sim.Data());
if(pData->isHiPACE()) {
delete pData; pData = NULL;
pData = PDataHiP::Get(sim.Data());
}
pData->LoadFileNames(timestep);
if(!pData->IsInit()) return;
PGlobals::Initialize();
TString opt = options;
// Open snapshot file and get the histograms
TString filename;
filename = Form("./%s/Plots/Snapshots/Snapshot-%s_%i.root",sim.Data(),sim.Data(),timestep);
TFile *ifile = (TFile*) gROOT->GetListOfFiles()->FindObject(filename.Data());
if (!ifile) ifile = new TFile(filename,"READ");
ifile->cd();
// Time in OU
Double_t Time = pData->GetRealTime();
cout << Form(" Getting histos..." );
// Electron density (plasma)
char hName[36];
sprintf(hName,"hDen2D_0");
TH2F *hDen2D = (TH2F*) ifile->Get(hName);
// Electron density species 2 (if any)
sprintf(hName,"hDen2D_1");
TH2F *hDen2D_1 = (TH2F*) ifile->Get(hName);
if(hDen2D_1)
hDen2D->Add(hDen2D_1,1);
// Electron density species 3 (if any)
sprintf(hName,"hDen2D_2");
TH2F *hDen2D_2 = (TH2F*) ifile->Get(hName);
if(hDen2D_2)
hDen2D->Add(hDen2D_2,1);
cout << Form(" done!" ) << endl;
// Get the sliced 1D histograms
Int_t NBinsZ = hDen2D->GetXaxis()->GetNbins();
Float_t zmin = hDen2D->GetXaxis()->GetBinLowEdge(1);
Float_t zmax = hDen2D->GetXaxis()->GetBinUpEdge(NBinsZ);
Float_t zrange = zmax-zmin;
Int_t NBinsX = hDen2D->GetYaxis()->GetNbins();
Float_t xmin = hDen2D->GetYaxis()->GetBinLowEdge(1);
Float_t xmax = hDen2D->GetYaxis()->GetBinUpEdge(NBinsX);
Float_t xrange = xmax-xmin;
// cout << Form(" Creating 2D histos..." );
// cout << Form(" done!" ) << endl;
cout << Form(" Allocating array with real data..." );
Int_t dims[2] = {NBinsZ,NBinsX};
Double_t *data = new Double_t[NBinsZ*NBinsX];
// TVirtualFFT::SetTransform(0);
cout << Form(" done!" ) << endl;
cout << Form(" Filling data aray..." );
for(Int_t i=0; i<NBinsZ; i++) {
for(Int_t j=0; j<NBinsX; j++) {
Int_t index = i * NBinsX + j;
data[index] = hDen2D->GetBinContent(i+1,j+1);
// substract ion background
data[index] -= 1;
}
}
cout << Form(" done!" ) << endl;
cout << Form(" Fourier transform ..." );
// TH2F *hFFTREb = new TH2F("hFFTREb","",NBinsZ,kzmin,kzmax,NBinsX,kxmin,kxmax);
// TH2F *hFFTIMb = new TH2F("hFFTIMb","",NBinsZ,kzmin,kzmax,NBinsX,kxmin,kxmax);
// TH2F *hFFTREb = new TH2F("hFFTREb","",NBinsZ,0.,NBinsZ,NBinsX,0.,NBinsX);
// TH2F *hFFTIMb = new TH2F("hFFTIMb","",NBinsZ,0.,NBinsZ,NBinsX,0.,NBinsX);
// TH2F *hFFTRE = 0;
// hFFTRE = (TH2F*) TH1::TransformHisto(fft, hFFTRE, "RE");
// hFFTRE->SetName("hFFTRE");
// TH2F *hFFTIM = 0;
// hFFTIM = (TH2F*) TH1::TransformHisto(fft, hFFTIM, "IM");
// hFFTIM->SetName("hFFTIM");
TVirtualFFT *fft = TVirtualFFT::FFT(2, dims, "R2C ES K");
fft->SetPoints(data);
fft->Transform();
cout << Form(" done!" ) << endl;
cout << Form(" Solving equation for potential in fourier space" ) << endl;
// \phi(kz,kx) = 1/(kz^2 + kx^2)
fft->GetPoints(data);
for(Int_t i=0; i<dims[0]; i++) {
for(Int_t j=0; j<(dims[1]/2+1); j++) {
Int_t index = 2 * (i * (dims[1]/2+1) + j);
Float_t kz;
if(i<dims[0]/2)
kz = TMath::Pi() * (i+0.5) / zrange;
else
kz = -TMath::Pi() * (dims[0]-i+0.5) / zrange;
Float_t kx = TMath::TwoPi() * (j+0.5) / xrange;
Float_t k2 = kx*kx + kz*kz;
data[index] /= k2;
data[index+1] /= k2;
}
}
cout << Form(" done!" ) << endl;
cout << Form(" Inverse Fourier transform ..." );
// backward transform:
TVirtualFFT *fft_back = TVirtualFFT::FFT(2, dims, "C2R ES K");
fft_back->SetPoints(data);
fft_back->Transform();
cout << Form(" done!" ) << endl;
Double_t *re_back = fft_back->GetPointsReal();
TH2F *hPhi2D = new TH2F("hPhi2D","",NBinsZ,zmin,zmax,NBinsX,xmin,xmax);
TH2F *hE2D_1_ifft = new TH2F("hE2D_1_ifft","",NBinsZ,zmin,zmax,NBinsX,xmin,xmax);
Double_t dx = hPhi2D->GetYaxis()->GetBinWidth(1);
for(Int_t i=0; i<NBinsZ; i++) {
for(Int_t j=0; j<NBinsX; j++) {
Int_t index = i * NBinsX + j;
hPhi2D->SetBinContent(i+1,j+1,re_back[index]);
Double_t der = 0.;
if(j>2 && j<=NBinsX-2) {
Int_t indjp1 = i * NBinsX + (j+1);
Int_t indjp2 = i * NBinsX + (j+2);
Int_t indjm1 = i * NBinsX + (j-1);
Int_t indjm2 = i * NBinsX + (j-2);
der = ( 4.0 / 3.0 * (re_back[indjp1] - re_back[indjm1]) / (2.0 * dx)
- 1.0 / 3.0 * (re_back[indjp2] - re_back[indjm2]) / (4.0 * dx) );
}
hE2D_1_ifft->SetBinContent(i+1,j+1,der);
}
}
hPhi2D->Scale(1.0/(NBinsZ*NBinsX));
hE2D_1_ifft->Scale(1.0/(NBinsZ*NBinsX));
TH2F *hE2D_0_ifft = new TH2F("hE2D_0_ifft","",NBinsZ,zmin,zmax,NBinsX,xmin,xmax);
Double_t dz = hPhi2D->GetXaxis()->GetBinWidth(1);
for(Int_t j=0; j<NBinsX; j++) {
for(Int_t i=0; i<NBinsZ; i++) {
Double_t der = 0.;
if(i>2 && j<=NBinsZ-2) {
Int_t indip1 = (i+1) * NBinsX + j;
Int_t indip2 = (i+2) * NBinsX + j;
Int_t indim1 = (i-1) * NBinsX + j;
Int_t indim2 = (i-2) * NBinsX + j;
der = ( 4.0 / 3.0 * (re_back[indip1] - re_back[indim1]) / (2.0 * dz)
- 1.0 / 3.0 * (re_back[indip2] - re_back[indim2]) / (4.0 * dz) );
}
hE2D_0_ifft->SetBinContent(i+1,j+1,der);
}
}
hE2D_0_ifft->Scale(1.0/(NBinsZ*NBinsX));
// TH2F *hPhi2D = 0;
// hPhi2D = (TH2F*) TH1::TransformHisto(fft_back, hPhi2D, "RE");
// hPhi2D->SetName("hPhi2D");
}
