Bug fix in the calculation of the mean curvature for the merged cosmic track
[u/mrichter/AliRoot.git] / STAT / TKDInterpolatorBase.cxx
CommitLineData
a3408ed3 1#include "TKDInterpolatorBase.h"
2#include "TKDNodeInfo.h"
3#include "TKDTree.h"
4
b6f6b31a 5#include "TROOT.h"
a3408ed3 6#include "TClonesArray.h"
7#include "TLinearFitter.h"
8#include "TTree.h"
9#include "TH2.h"
10#include "TObjArray.h"
11#include "TObjString.h"
a3408ed3 12#include "TMath.h"
13#include "TVectorD.h"
14#include "TMatrixD.h"
15
16ClassImp(TKDInterpolatorBase)
17
18/////////////////////////////////////////////////////////////////////
19// Memory setup of protected data members
20// fRefPoints : evaluation point of PDF for each terminal node of underlying KD Tree.
21// | 1st terminal node (fNDim point coordinates) | 2nd terminal node (fNDim point coordinates) | ...
22//
23// fRefValues : evaluation value/error of PDF for each terminal node of underlying KD Tree.
24// | 1st terminal node (value) | 2nd terminal node (value) | ... | 1st terminal node (error) | 2nd terminal node (error) | ...
25//
26// status = |0|0|0|0|0|1(tri-cubic weights)|1(STORE)|1 INT(0 COG )|
27/////////////////////////////////////////////////////////////////////
28
29
30//_________________________________________________________________
1a439134 31TKDInterpolatorBase::TKDInterpolatorBase(Int_t dim) :
50c4eb3a 32 fNSize(dim)
33 ,fNTNodes(0)
34 ,fTNodes(0x0)
b6f6b31a 35 ,fTNodesDraw(0x0)
b273c7cb 36 ,fStatus(0)
50c4eb3a 37 ,fLambda(1 + dim + (dim*(dim+1)>>1))
38 ,fDepth(-1)
39 ,fAlpha(.5)
40 ,fRefPoints(0x0)
41 ,fBuffer(0x0)
42 ,fKDhelper(0x0)
43 ,fFitter(0x0)
a3408ed3 44{
45// Default constructor. To be used with care since in this case building
46// of data structure is completly left to the user responsability.
b273c7cb 47 UseWeights();
a3408ed3 48}
49
50//_________________________________________________________________
1a439134 51void TKDInterpolatorBase::Build(Int_t n)
a3408ed3 52{
50c4eb3a 53 // allocate memory for data
a3408ed3 54
50c4eb3a 55 if(fTNodes) delete fTNodes;
56 fNTNodes = n;
53ee3cad 57 // check granularity
58 if(Int_t((1.+fAlpha)*fLambda) > fNTNodes){
59 Warning("TKDInterpolatorBase::Build()", Form("Minimum number of points [%d] needed for interpolation exceeds number of evaluation points [%d]. Please increase granularity.", Int_t((1.+fAlpha)*fLambda), fNTNodes));
60 }
50c4eb3a 61 fTNodes = new TClonesArray("TKDNodeInfo", fNTNodes);
62 for(int in=0; in<fNTNodes; in++) new ((*fTNodes)[in]) TKDNodeInfo(fNSize);
a3408ed3 63}
64
65//_________________________________________________________________
66TKDInterpolatorBase::~TKDInterpolatorBase()
67{
50c4eb3a 68 if(fFitter) delete fFitter;
69 if(fKDhelper) delete fKDhelper;
70 if(fBuffer) delete [] fBuffer;
71
72 if(fRefPoints){
73 for(int idim=0; idim<fNSize; idim++) delete [] fRefPoints[idim] ;
74 delete [] fRefPoints;
75 }
b6f6b31a 76 if(fTNodes){
77 fTNodes->Delete();
78 delete fTNodes;
79 }
80 delete [] fTNodesDraw;
81
82 TH2 *h2=0x0;
83 if((h2 = (TH2S*)gROOT->FindObject("hKDnodes"))) delete h2;
a3408ed3 84}
85
86
87//__________________________________________________________________
88Bool_t TKDInterpolatorBase::GetCOGPoint(Int_t inode, Float_t *&coord, Float_t &val, Float_t &err) const
89{
50c4eb3a 90 if(inode < 0 || inode > fNTNodes) return kFALSE;
a3408ed3 91
50c4eb3a 92 TKDNodeInfo *node = (TKDNodeInfo*)(*fTNodes)[inode];
93 coord = &(node->Data()[0]);
94 val = node->Val()[0];
95 err = node->Val()[1];
96 return kTRUE;
a3408ed3 97}
98
99//_________________________________________________________________
1a439134 100TKDNodeInfo* TKDInterpolatorBase::GetNodeInfo(Int_t inode) const
a3408ed3 101{
50c4eb3a 102 if(!fTNodes || inode >= fNTNodes) return 0x0;
103 return (TKDNodeInfo*)(*fTNodes)[inode];
a3408ed3 104}
105
b273c7cb 106//_________________________________________________________________
107Bool_t TKDInterpolatorBase::GetRange(Int_t ax, Float_t &min, Float_t &max) const
108{
109 if(!fTNodes) return kFALSE;
110 Int_t ndim = ((TKDNodeInfo*)(*fTNodes)[0])->GetDimension();
111 if(ax<0 || ax>=ndim){
112 min=0.; max=0.;
113 return kFALSE;
114 }
115 min=1.e10; max=-1.e10;
116 Float_t axmin, axmax;
117 for(Int_t in=fNTNodes; in--; ){
118 TKDNodeInfo *node = (TKDNodeInfo*)((*fTNodes)[in]);
119 node->GetBoundary(ax, axmin, axmax);
120 if(axmin<min) min = axmin;
121 if(axmax>max) max = axmax;
122 }
123
124 return kTRUE;
125}
a3408ed3 126
127//__________________________________________________________________
b273c7cb 128void TKDInterpolatorBase::GetStatus(Option_t *opt)
a3408ed3 129{
130// Prints the status of the interpolator
131
b273c7cb 132 printf("Interpolator Status[%d] :\n", fStatus);
50c4eb3a 133 printf(" Dim : %d [%d]\n", fNSize, fLambda);
b273c7cb 134 printf(" Method : %s\n", UseCOG() ? "COG" : "INT");
135 printf(" Store : %s\n", HasStore() ? "YES" : "NO");
136 printf(" Weights: %s\n", UseWeights() ? "YES" : "NO");
50c4eb3a 137
b273c7cb 138 if(strcmp(opt, "all") != 0 ) return;
50c4eb3a 139 printf("fNTNodes %d\n", fNTNodes); //Number of evaluation data points
140 for(int i=0; i<fNTNodes; i++){
141 TKDNodeInfo *node = (TKDNodeInfo*)(*fTNodes)[i];
142 printf("%d ", i); node->Print();
143 }
a3408ed3 144}
145
146//_________________________________________________________________
147Double_t TKDInterpolatorBase::Eval(const Double_t *point, Double_t &result, Double_t &error, Bool_t force)
148{
149// Evaluate PDF for "point". The result is returned in "result" and error in "error". The function returns the chi2 of the fit.
150//
151// Observations:
152//
153// 1. The default method used for interpolation is kCOG.
154// 2. The initial number of neighbors used for the estimation is set to Int(alpha*fLambda) (alpha = 1.5)
50c4eb3a 155
156 Float_t pointF[50]; // local Float_t conversion for "point"
157 for(int idim=0; idim<fNSize; idim++) pointF[idim] = (Float_t)point[idim];
158 Int_t nodeIndex = GetNodeIndex(pointF);
159 if(nodeIndex<0){
53ee3cad 160 Error("TKDInterpolatorBase::Eval()", "Can not retrive node for data point.");
50c4eb3a 161 result = 0.;
162 error = 1.E10;
163 return 0.;
164 }
165 TKDNodeInfo *node = (TKDNodeInfo*)(*fTNodes)[nodeIndex];
b273c7cb 166 if(node->Cov() && !force) return node->CookPDF(point, result, error);
50c4eb3a 167
168 // Allocate memory
169 if(!fBuffer) fBuffer = new Double_t[2*fLambda];
170 if(!fKDhelper){
171 fRefPoints = new Float_t*[fNSize];
172 for(int id=0; id<fNSize; id++){
173 fRefPoints[id] = new Float_t[fNTNodes];
174 for(int in=0; in<fNTNodes; in++) fRefPoints[id][in] = ((TKDNodeInfo*)(*fTNodes)[in])->Data()[id];
175 }
b273c7cb 176 Info("TKDInterpolatorBase::Eval()", Form("Build TKDTree(%d, %d, %d)", fNTNodes, fNSize, kNhelper));
53ee3cad 177 fKDhelper = new TKDTreeIF(fNTNodes, fNSize, kNhelper, fRefPoints);
178 fKDhelper->Build();
179 fKDhelper->MakeBoundariesExact();
50c4eb3a 180 }
181 if(!fFitter) fFitter = new TLinearFitter(fLambda, Form("hyp%d", fLambda-1));
182
183 // generate parabolic for nD
184 //Float_t alpha = Float_t(2*lambda + 1) / fNTNodes; // the bandwidth or smoothing parameter
185 //Int_t npoints = Int_t(alpha * fNTNodes);
186 //printf("Params : %d NPoints %d\n", lambda, npoints);
187 // prepare workers
188
189 Int_t ipar, // local looping variable
53ee3cad 190 npoints_new = Int_t((1.+fAlpha)*fLambda),
191 npoints(0); // number of data points used for interpolation
192 Int_t *index = new Int_t[2*npoints_new]; // indexes of NN
193 Float_t *dist = new Float_t[2*npoints_new], // distances of NN
50c4eb3a 194 d, // NN normalized distance
195 w0, // work
196 w; // tri-cubic weight function
197
53ee3cad 198 Bool_t kDOWN = kFALSE;
50c4eb3a 199 do{
b273c7cb 200 if(npoints){
201 Info("TKDInterpolatorBase::Eval()", Form("Interpolation failed. Trying to increase the number of interpolation points from %d to %d.", npoints, npoints_new));
202 }
53ee3cad 203 if(npoints == npoints_new){
204 Error("TKDInterpolatorBase::Eval()", Form("Interpolation failed and number of interpolation points (%d) Can not be increased further.", npoints));
205 result = 0.;
206 error = 1.E10;
207 return 0.;
208 } else npoints = npoints_new;
209 if(npoints > fNTNodes){
210 Warning("TKDInterpolatorBase::Eval()", Form("The number of interpolation points requested (%d) exceeds number of PDF values (%d). Downscale.", npoints, fNTNodes));
211 npoints = fNTNodes;
212 kDOWN = kTRUE;
213 }
214
50c4eb3a 215 // find nearest neighbors
216 for(int idim=0; idim<fNSize; idim++) pointF[idim] = (Float_t)point[idim];
217 fKDhelper->FindNearestNeighbors(pointF, npoints+1, index, dist);
53ee3cad 218
50c4eb3a 219 // add points to fitter
220 fFitter->ClearPoints();
221 TKDNodeInfo *tnode = 0x0;
222 for(int in=0; in<npoints; in++){
223 tnode = (TKDNodeInfo*)(*fTNodes)[index[in]];
224 //tnode->Print();
b273c7cb 225 if(UseCOG()){ // COG
226 Float_t *p = &(tnode->Data()[0]);
227 ipar = 0;
228 for(int idim=0; idim<fNSize; idim++){
229 fBuffer[ipar++] = p[idim];
230 for(int jdim=idim; jdim<fNSize; jdim++) fBuffer[ipar++] = p[idim]*p[jdim];
231 }
232 } else { // INT
50c4eb3a 233 Float_t *bounds = &(tnode->Data()[fNSize]);
234 ipar = 0;
235 for(int idim=0; idim<fNSize; idim++){
236 fBuffer[ipar++] = .5*(bounds[2*idim] + bounds[2*idim+1]);
237 fBuffer[ipar++] = (bounds[2*idim]*bounds[2*idim] + bounds[2*idim] * bounds[2*idim+1] + bounds[2*idim+1] * bounds[2*idim+1])/3.;
238 for(int jdim=idim+1; jdim<fNSize; jdim++) fBuffer[ipar++] = (bounds[2*idim] + bounds[2*idim+1]) * (bounds[2*jdim] + bounds[2*jdim+1]) * .25;
239 }
50c4eb3a 240 }
241
242 // calculate tri-cubic weighting function
b273c7cb 243 if(UseWeights()){
244 d = dist[in]/dist[npoints];
50c4eb3a 245 w0 = (1. - d*d*d); w = w0*w0*w0;
b273c7cb 246 if(w<1.e-30) continue;
50c4eb3a 247 } else w = 1.;
248
b273c7cb 249// printf("%2d d[%f] w[%f] x[", index[in], d, w);
53ee3cad 250// for(int idim=0; idim<fLambda-1; idim++) printf("%f ", fBuffer[idim]);
b273c7cb 251// printf("]\n"); printf("v[%f +- %f] (%f, %f)\n", tnode->Val()[0], tnode->Val()[1]/w, tnode->Val()[1], w);
50c4eb3a 252 fFitter->AddPoint(fBuffer, tnode->Val()[0], tnode->Val()[1]/w);
253 }
53ee3cad 254 npoints_new = npoints+ (kDOWN ? 0 : kdN);
50c4eb3a 255 } while(fFitter->Eval());
256 delete [] index;
257 delete [] dist;
258
259 // retrive fitter results
260 TMatrixD cov(fLambda, fLambda);
261 TVectorD par(fLambda);
262 fFitter->GetCovarianceMatrix(cov);
263 fFitter->GetParameters(par);
264 Double_t chi2 = fFitter->GetChisquare()/(npoints - 4 - fLambda);
265
266 // store results
b273c7cb 267 if(HasStore()) node->Store(par, cov);
50c4eb3a 268
269 // Build df/dpi|x values
270 Double_t *fdfdp = &fBuffer[fLambda];
271 ipar = 0;
272 fdfdp[ipar++] = 1.;
273 for(int idim=0; idim<fNSize; idim++){
274 fdfdp[ipar++] = point[idim];
275 for(int jdim=idim; jdim<fNSize; jdim++) fdfdp[ipar++] = point[idim]*point[jdim];
276 }
277
278 // calculate estimation
279 result =0.; error = 0.;
280 for(int i=0; i<fLambda; i++){
281 result += fdfdp[i]*par(i);
282 for(int j=0; j<fLambda; j++) error += fdfdp[i]*fdfdp[j]*cov(i,j);
283 }
284 error = TMath::Sqrt(error);
285
286 return chi2;
a3408ed3 287}
288
289//_________________________________________________________________
b273c7cb 290void TKDInterpolatorBase::DrawProjection(UInt_t ax1, UInt_t ax2)
a3408ed3 291{
292// Draw nodes structure projected on plane "ax1:ax2". The parameter
293// "depth" specifies the bucket size per node. If depth == -1 draw only
294// terminal nodes and evaluation points (default -1 i.e. bucket size per node equal bucket size specified by the user)
295//
50c4eb3a 296
b273c7cb 297 Float_t ax1min, ax1max, ax2min, ax2max;
298 GetRange(ax1, ax1min, ax1max);
299 GetRange(ax2, ax2min, ax2max);
b6f6b31a 300 TH2 *h2 = 0x0;
b273c7cb 301 if(!(h2 = (TH2S*)gROOT->FindObject("hKDnodes"))){
b6f6b31a 302 h2 = new TH2S("hKDnodes", "", 100, ax1min, ax1max, 100, ax2min, ax2max);
b6f6b31a 303 }
b273c7cb 304 h2->GetXaxis()->SetRangeUser(ax1min, ax1max);
305 h2->GetXaxis()->SetTitle(Form("x_{%d}", ax1));
306 h2->GetYaxis()->SetRangeUser(ax2min, ax2max);
307 h2->GetYaxis()->SetTitle(Form("x_{%d}", ax2));
50c4eb3a 308 h2->Draw();
b273c7cb 309
50c4eb3a 310
b6f6b31a 311 if(!fTNodesDraw) fTNodesDraw = new TKDNodeInfo::TKDNodeDraw[fNTNodes];
312 TKDNodeInfo::TKDNodeDraw *box = 0x0;
b273c7cb 313 for(Int_t in=fNTNodes; in--; ){
b6f6b31a 314 box = &(fTNodesDraw[in]);
b273c7cb 315 box->SetNode((TKDNodeInfo*)((*fTNodes)[in]), fNSize, ax1, ax2);
b6f6b31a 316 box->Draw();
50c4eb3a 317 }
b273c7cb 318
50c4eb3a 319 return;
a3408ed3 320}
321
53ee3cad 322//_________________________________________________________________
323void TKDInterpolatorBase::SetAlpha(Float_t a)
324{
325 if(a<0.5){
326 Warning("TKDInterpolatorBase::SetAlpha()", "The scale parameter has to be larger than 0.5");
327 fAlpha = 0.5;
328 return;
329 }
330 // check value
331 if(Int_t((a+1.)*fLambda) > fNTNodes){
332 fAlpha = TMath::Max(0.5, Float_t(fNTNodes)/fLambda-1.);
333 Warning("TKDInterpolatorBase::SetAlpha()", Form("Interpolation neighborhood exceeds number of evaluation points. Downscale alpha to %f", fAlpha));
334 printf("n[%d] nodes[%d]\n", Int_t((fAlpha+1.)*fLambda), fNTNodes);
335 return;
336 }
337 fAlpha = a;
338 return;
339}
340