| 1 |
// $Id: PUReweighting.cc,v 1.1 2011/06/01 12:36:59 mzanetti Exp $
|
| 2 |
|
| 3 |
|
| 4 |
#include "MitPhysics/Utils/interface/PUReweightingMulti.h"
|
| 5 |
#include <TAxis.h>
|
| 6 |
|
| 7 |
ClassImp(mithep::PUReweightingMulti)
|
| 8 |
|
| 9 |
using namespace mithep;
|
| 10 |
|
| 11 |
|
| 12 |
PUReweightingMulti::PUReweightingMulti(const THnSparse *sparse, int maxn, double minprob) :
|
| 13 |
fSparse(sparse),
|
| 14 |
fNsBins(0),
|
| 15 |
fNDim(0),
|
| 16 |
fMaxN(maxn+1),
|
| 17 |
fMinProb(minprob),
|
| 18 |
fWeights(0),
|
| 19 |
fIndices(0),
|
| 20 |
fCache(0)
|
| 21 |
{
|
| 22 |
|
| 23 |
Setup();
|
| 24 |
|
| 25 |
}
|
| 26 |
|
| 27 |
PUReweightingMulti::~PUReweightingMulti() {
|
| 28 |
|
| 29 |
if (fWeights) delete [] fWeights;
|
| 30 |
if (fIndices) delete [] fIndices;
|
| 31 |
if (fCache) delete [] fCache;
|
| 32 |
if (fOffsets) delete [] fOffsets;
|
| 33 |
if (fIndOffsets) delete [] fIndOffsets;
|
| 34 |
if (fFactors) delete [] fFactors;
|
| 35 |
|
| 36 |
|
| 37 |
}
|
| 38 |
|
| 39 |
void PUReweightingMulti::Setup() {
|
| 40 |
|
| 41 |
//cache all values needed to quickly computed probability density as sum over bins of the sparse histogram
|
| 42 |
|
| 43 |
fNsBins = fSparse->GetNbins();
|
| 44 |
fNDim = fSparse->GetNdimensions();
|
| 45 |
|
| 46 |
fOffsets = new Int_t[fNDim];
|
| 47 |
fIndOffsets = new Int_t[fNDim];
|
| 48 |
fFactors = new Double_t[fNDim];
|
| 49 |
|
| 50 |
fWeights = new Double_t[fNsBins];
|
| 51 |
fIndices = new UShort_t[fNDim*fNsBins];
|
| 52 |
|
| 53 |
int nbinstotal = 0;
|
| 54 |
int *cacheoffset = new int[fNDim];
|
| 55 |
for (int idim=0; idim<fNDim; ++idim) {
|
| 56 |
cacheoffset[idim] = nbinstotal;
|
| 57 |
nbinstotal += fSparse->GetAxis(idim)->GetNbins()+1;
|
| 58 |
fIndOffsets[idim] = fNsBins*idim;
|
| 59 |
}
|
| 60 |
fNCacheBins = nbinstotal;
|
| 61 |
fCache = new Double_t[fMaxN*fNCacheBins];
|
| 62 |
for (int idim=0; idim<fNDim; ++idim) {
|
| 63 |
int nbins = fSparse->GetAxis(idim)->GetNbins()+1;
|
| 64 |
for (int ibin=0; ibin<nbins; ++ibin) {
|
| 65 |
double lambda = (ibin>0) ? exp(fSparse->GetAxis(idim)->GetBinCenter(ibin)) : 0.0;
|
| 66 |
for (int n=0; n<fMaxN; ++n) {
|
| 67 |
int globalbin = cacheoffset[idim] + ibin;
|
| 68 |
//fCache[fMaxN*globalbin + n] = TMath::Poisson(n,lambda);
|
| 69 |
double val = TMath::Poisson(n,lambda);
|
| 70 |
fCache[fNCacheBins*n + globalbin] = (val > fMinProb) ? val : 0.0;
|
| 71 |
}
|
| 72 |
}
|
| 73 |
}
|
| 74 |
|
| 75 |
int *coords = new int[fNDim];
|
| 76 |
double sumweights = 0;
|
| 77 |
for (int i=0; i<fNsBins; ++i) {
|
| 78 |
sumweights += fSparse->GetBinContent(i,coords);
|
| 79 |
}
|
| 80 |
|
| 81 |
for (int i=0; i<fNsBins; ++i) {
|
| 82 |
double weight = fSparse->GetBinContent(i,coords);
|
| 83 |
fWeights[i] = weight/sumweights;
|
| 84 |
for (int idim=0; idim<fNDim; ++idim) {
|
| 85 |
//fIndices[fNDim*i + idim] = cacheoffset[idim] + coords[idim];
|
| 86 |
fIndices[fNsBins*idim + i] = cacheoffset[idim] + coords[idim];
|
| 87 |
}
|
| 88 |
}
|
| 89 |
|
| 90 |
delete[] cacheoffset;
|
| 91 |
delete[] coords;
|
| 92 |
|
| 93 |
}
|
| 94 |
|
| 95 |
double PUReweightingMulti::TargetPdf(int *npus, int ndim) const {
|
| 96 |
|
| 97 |
assert(ndim<=fNDim);
|
| 98 |
|
| 99 |
for (int idim=0; idim<ndim; ++idim) {
|
| 100 |
if (npus[idim] >= fMaxN) return 0.0;
|
| 101 |
fOffsets[idim] = fNCacheBins*npus[idim];
|
| 102 |
}
|
| 103 |
|
| 104 |
double totalweight = 0.0;
|
| 105 |
for (int i=0; i<fNsBins; ++i) {
|
| 106 |
bool nonzero = true;
|
| 107 |
for (int idim=0; idim<ndim; ++idim) {
|
| 108 |
fFactors[idim] = fCache[fOffsets[idim]+fIndices[fIndOffsets[idim]+i]];
|
| 109 |
if ( !(fFactors[idim]>0.0) ) {
|
| 110 |
nonzero = false;
|
| 111 |
break;
|
| 112 |
}
|
| 113 |
}
|
| 114 |
if (nonzero) {
|
| 115 |
double weight = fWeights[i];
|
| 116 |
for (int idim=0; idim<ndim; ++idim) {
|
| 117 |
weight *= fFactors[idim];
|
| 118 |
}
|
| 119 |
totalweight += weight;
|
| 120 |
}
|
| 121 |
}
|
| 122 |
|
| 123 |
return totalweight;
|
| 124 |
}
|
| 125 |
|
| 126 |
TH3D *PUReweightingMulti::Target3D() {
|
| 127 |
assert(fNDim>=3);
|
| 128 |
|
| 129 |
int np[3];
|
| 130 |
|
| 131 |
TH3D *target3d = new TH3D("target3d","",fMaxN,-0.5,fMaxN-0.5,fMaxN,-0.5,fMaxN-0.5,fMaxN,-0.5,fMaxN-0.5);
|
| 132 |
for (int i=0; i<fMaxN; ++i) {
|
| 133 |
np[0] = i;
|
| 134 |
for (int j=0; j<fMaxN; ++j) {
|
| 135 |
np[1] = j;
|
| 136 |
for (int k=0; k<fMaxN; ++k) {
|
| 137 |
np[2] = k;
|
| 138 |
target3d->Fill(i,j,k,TargetPdf(np,3));
|
| 139 |
}
|
| 140 |
}
|
| 141 |
}
|
| 142 |
return target3d;
|
| 143 |
|
| 144 |
}
|
| 145 |
|
| 146 |
TH3D *PUReweightingMulti::Weights3D(const TH3D *source3d) {
|
| 147 |
assert(fNDim>=3);
|
| 148 |
|
| 149 |
TH3D *source3dclone = (TH3D*)source3d->Clone();
|
| 150 |
source3dclone->Scale(1.0/source3dclone->GetSumOfWeights());
|
| 151 |
|
| 152 |
int np[3];
|
| 153 |
TH3D *target3d = new TH3D("target3dtemp","",fMaxN,-0.5,fMaxN-0.5,fMaxN,-0.5,fMaxN-0.5,fMaxN,-0.5,fMaxN-0.5);
|
| 154 |
for (int i=0; i<fMaxN; ++i) {
|
| 155 |
np[0] = i;
|
| 156 |
for (int j=0; j<fMaxN; ++j) {
|
| 157 |
np[1] = j;
|
| 158 |
for (int k=0; k<fMaxN; ++k) {
|
| 159 |
np[2] = k;
|
| 160 |
if (source3dclone->GetBinContent(source3dclone->FindFixBin(i,j,k))>0.0) {
|
| 161 |
target3d->Fill(i,j,k,TargetPdf(np,3));
|
| 162 |
}
|
| 163 |
else {
|
| 164 |
target3d->Fill(i,j,k,0.0);
|
| 165 |
}
|
| 166 |
}
|
| 167 |
}
|
| 168 |
}
|
| 169 |
target3d->Scale(1.0/target3d->GetSumOfWeights());
|
| 170 |
|
| 171 |
TH3D *weights3d = new TH3D(*target3d / *source3dclone);
|
| 172 |
delete source3dclone;
|
| 173 |
return weights3d;
|
| 174 |
|
| 175 |
} |
