// @(#)root/graf:$Name: $:$Id: TSpline.cxx,v 1.12 2005/11/21 13:57:42 couet Exp $
// Author: Federico Carminati 28/02/2000
/*************************************************************************
* Copyright (C) 1995-2000, Rene Brun and Fons Rademakers. *
* All rights reserved. *
* *
* For the licensing terms see $ROOTSYS/LICENSE. *
* For the list of contributors see $ROOTSYS/README/CREDITS. *
*************************************************************************/
//////////////////////////////////////////////////////////////////////////
// //
// TSpline //
// //
// Base class for spline implementation containing the Draw/Paint //
// methods //
// //
//////////////////////////////////////////////////////////////////////////
#include "TSpline.h"
#include "TVirtualPad.h"
#include "TF1.h"
#include "TSystem.h"
#include "Riostream.h"
ClassImp(TSplinePoly)
ClassImp(TSplinePoly3)
ClassImp(TSplinePoly5)
ClassImp(TSpline3)
ClassImp(TSpline5)
ClassImp(TSpline)
//____________________________________________________________________________
void TSpline::Draw(Option_t *option)
{
// Draw this function with its current attributes.
//
// Possible option values are:
// "SAME" superimpose on top of existing picture
// "L" connect all computed points with a straight line
// "C" connect all computed points with a smooth curve.
// "P" add a polymarker at each knot
//
// Note that the default value is "L". Therefore to draw on top
// of an existing picture, specify option "LSAME"
TString opt = option;
opt.ToLower();
if (gPad && !opt.Contains("same")) gPad->Clear();
AppendPad(option);
}
//____________________________________________________________________________
void TSpline::Paint(Option_t *option)
{
// Paint this function with its current attributes.
Int_t i;
Double_t xv;
TString opt = option;
opt.ToLower();
Double_t xmin, xmax, pmin, pmax;
pmin = gPad->PadtoX(gPad->GetUxmin());
pmax = gPad->PadtoX(gPad->GetUxmax());
xmin = fXmin;
xmax = fXmax;
if (opt.Contains("same")) {
if (xmax < pmin) return; // Otto: completely outside
if (xmin > pmax) return;
if (xmin < pmin) xmin = pmin;
if (xmax > pmax) xmax = pmax;
} else {
gPad->Clear();
}
// Create a temporary histogram and fill each channel with the function value
if (fHistogram)
if ((!gPad->GetLogx() && fHistogram->TestBit(TH1::kLogX)) ||
(gPad->GetLogx() && !fHistogram->TestBit(TH1::kLogX)))
{ delete fHistogram; fHistogram = 0;}
if (fHistogram) {
//if (xmin != fXmin || xmax != fXmax)
fHistogram->GetXaxis()->SetLimits(xmin,xmax);
} else {
// if logx, we must bin in logx and not in x !!!
// otherwise if several decades, one gets crazy results
if (xmin > 0 && gPad->GetLogx()) {
Double_t *xbins = new Double_t[fNpx+1];
Double_t xlogmin = TMath::Log10(xmin);
Double_t xlogmax = TMath::Log10(xmax);
Double_t dlogx = (xlogmax-xlogmin)/((Double_t)fNpx);
for (i=0;i<=fNpx;i++) {
xbins[i] = gPad->PadtoX(xlogmin+ i*dlogx);
}
fHistogram = new TH1F("Spline",GetTitle(),fNpx,xbins);
fHistogram->SetBit(TH1::kLogX);
delete [] xbins;
} else {
fHistogram = new TH1F("Spline",GetTitle(),fNpx,xmin,xmax);
}
if (!fHistogram) return;
fHistogram->SetDirectory(0);
}
for (i=1;i<=fNpx;i++) {
xv = fHistogram->GetBinCenter(i);
fHistogram->SetBinContent(i,this->Eval(xv));
}
// Copy Function attributes to histogram attributes
fHistogram->SetBit(TH1::kNoStats);
fHistogram->SetLineColor(GetLineColor());
fHistogram->SetLineStyle(GetLineStyle());
fHistogram->SetLineWidth(GetLineWidth());
fHistogram->SetFillColor(GetFillColor());
fHistogram->SetFillStyle(GetFillStyle());
fHistogram->SetMarkerColor(GetMarkerColor());
fHistogram->SetMarkerStyle(GetMarkerStyle());
fHistogram->SetMarkerSize(GetMarkerSize());
// Draw the histogram
// but first strip off the 'p' option if any
char *o = (char *) opt.Data();
Int_t j=0;
i=0;
Bool_t graph=kFALSE;
do
if(o[i]=='p') graph=kTRUE ; else o[j++]=o[i];
while(o[i++]);
if (opt.Length() == 0 ) fHistogram->Paint("lf");
else if (opt == "same") fHistogram->Paint("lfsame");
else fHistogram->Paint(opt.Data());
// Think about the graph, if demanded
if(graph) {
if(!fGraph) {
Double_t *xx = new Double_t[fNp];
Double_t *yy = new Double_t[fNp];
for(i=0; i<fNp; ++i)
GetKnot(i,xx[i],yy[i]);
fGraph=new TGraph(fNp,xx,yy);
delete [] xx;
delete [] yy;
}
fGraph->SetMarkerColor(GetMarkerColor());
fGraph->SetMarkerStyle(GetMarkerStyle());
fGraph->SetMarkerSize(GetMarkerSize());
fGraph->Paint("p");
}
}
//______________________________________________________________________________
void TSpline::Streamer(TBuffer &R__b)
{
// Stream an object of class TSpline.
if (R__b.IsReading()) {
UInt_t R__s, R__c;
Version_t R__v = R__b.ReadVersion(&R__s, &R__c);
if (R__v > 1) {
TSpline::Class()->ReadBuffer(R__b, this, R__v, R__s, R__c);
return;
}
//====process old versions before automatic schema evolution
TNamed::Streamer(R__b);
TAttLine::Streamer(R__b);
TAttFill::Streamer(R__b);
TAttMarker::Streamer(R__b);
fNp = 0;
/*
R__b >> fDelta;
R__b >> fXmin;
R__b >> fXmax;
R__b >> fNp;
R__b >> fKstep;
R__b >> fHistogram;
R__b >> fGraph;
R__b >> fNpx;
*/
R__b.CheckByteCount(R__s, R__c, TSpline::IsA());
//====end of old versions
} else {
TSpline::Class()->WriteBuffer(R__b,this);
}
}
//////////////////////////////////////////////////////////////////////////
// //
// TSpline3 //
// //
// Class to create third splines to interpolate knots //
// Arbitrary conditions can be introduced for first and second //
// derivatives at beginning and ending points //
// //
//////////////////////////////////////////////////////////////////////////
//____________________________________________________________________________
TSpline3::TSpline3(const char *title,
Double_t x[], Double_t y[], Int_t n, const char *opt,
Double_t valbeg, Double_t valend) :
TSpline(title,-1,x[0],x[n-1],n,kFALSE),
fValBeg(valbeg), fValEnd(valend), fBegCond(0), fEndCond(0)
{
// Third spline creator given an array of
// arbitrary knots in increasing abscissa order and
// possibly end point conditions
fName="Spline3";
// Set endpoint conditions
if(opt) SetCond(opt);
// Create the plynomial terms and fill
// them with node information
fPoly = new TSplinePoly3[n];
for (Int_t i=0; i<n; ++i) {
fPoly[i].X() = x[i];
fPoly[i].Y() = y[i];
}
// Build the spline coefficients
BuildCoeff();
}
//____________________________________________________________________________
TSpline3::TSpline3(const char *title,
Double_t xmin, Double_t xmax,
Double_t y[], Int_t n, const char *opt,
Double_t valbeg, Double_t valend) :
TSpline(title,(xmax-xmin)/(n-1), xmin, xmax, n, kTRUE),
fValBeg(valbeg), fValEnd(valend),
fBegCond(0), fEndCond(0)
{
// Third spline creator given an array of
// arbitrary function values on equidistant n abscissa
// values from xmin to xmax and possibly end point conditions
fName="Spline3";
// Set endpoint conditions
if(opt) SetCond(opt);
// Create the plynomial terms and fill
// them with node information
fPoly = new TSplinePoly3[n];
for (Int_t i=0; i<n; ++i) {
fPoly[i].X() = fXmin+i*fDelta;
fPoly[i].Y() = y[i];
}
// Build the spline coefficients
BuildCoeff();
}
//____________________________________________________________________________
TSpline3::TSpline3(const char *title,
Double_t x[], const TF1 *func, Int_t n, const char *opt,
Double_t valbeg, Double_t valend) :
TSpline(title,-1, x[0], x[n-1], n, kFALSE),
fValBeg(valbeg), fValEnd(valend),
fBegCond(0), fEndCond(0)
{
// Third spline creator given an array of
// arbitrary abscissas in increasing order and a function
// to interpolate and possibly end point conditions
fName="Spline3";
// Set endpoint conditions
if(opt) SetCond(opt);
// Create the plynomial terms and fill
// them with node information
fPoly = new TSplinePoly3[n];
for (Int_t i=0; i<n; ++i) {
fPoly[i].X() = x[i];
fPoly[i].Y() = ((TF1*)func)->Eval(x[i]);
}
// Build the spline coefficients
BuildCoeff();
}
//____________________________________________________________________________
TSpline3::TSpline3(const char *title,
Double_t xmin, Double_t xmax,
const TF1 *func, Int_t n, const char *opt,
Double_t valbeg, Double_t valend) :
TSpline(title,(xmax-xmin)/(n-1), xmin, xmax, n, kTRUE),
fValBeg(valbeg), fValEnd(valend),
fBegCond(0), fEndCond(0)
{
// Third spline creator given a function to be
// evaluated on n equidistand abscissa points between xmin
// and xmax and possibly end point conditions
fName="Spline3";
// Set endpoint conditions
if(opt) SetCond(opt);
// Create the plynomial terms and fill
// them with node information
fPoly = new TSplinePoly3[n];
for (Int_t i=0; i<n; ++i) {
Double_t x=fXmin+i*fDelta;
fPoly[i].X() = x;
fPoly[i].Y() = ((TF1*)func)->Eval(x);
}
// Build the spline coefficients
BuildCoeff();
}
//____________________________________________________________________________
TSpline3::TSpline3(const char *title,
const TGraph *g, const char *opt,
Double_t valbeg, Double_t valend) :
TSpline(title,-1,0,0,g->GetN(),kFALSE),
fValBeg(valbeg), fValEnd(valend),
fBegCond(0), fEndCond(0)
{
// Third spline creator given a TGraph with
// abscissa in increasing order and possibly end
// point conditions
fName="Spline3";
// Set endpoint conditions
if(opt) SetCond(opt);
// Create the plynomial terms and fill
// them with node information
fPoly = new TSplinePoly3[fNp];
for (Int_t i=0; i<fNp; ++i) {
Double_t xx, yy;
g->GetPoint(i,xx,yy);
fPoly[i].X()=xx;
fPoly[i].Y()=yy;
}
fXmin = fPoly[0].X();
fXmax = fPoly[fNp-1].X();
// Build the spline coefficients
BuildCoeff();
}
//____________________________________________________________________________
void TSpline3::SetCond(const char *opt)
{
// Check the boundary conditions
const char *b1 = strstr(opt,"b1");
const char *e1 = strstr(opt,"e1");
const char *b2 = strstr(opt,"b2");
const char *e2 = strstr(opt,"e2");
if (b1 && b2)
Error("SetCond","Cannot specify first and second derivative at first point");
if (e1 && e2)
Error("SetCond","Cannot specify first and second derivative at last point");
if (b1) fBegCond=1;
else if (b2) fBegCond=2;
if (e1) fEndCond=1;
else if (e2) fEndCond=2;
}
//___________________________________________________________________________
void TSpline3::Test()
{
// Test method for TSpline5
//
// n number of data points.
// m 2*m-1 is order of spline.
// m = 2 always for third spline.
// nn,nm1,mm,
// mm1,i,k,
// j,jj temporary integer variables.
// z,p temporary double precision variables.
// x[n] the sequence of knots.
// y[n] the prescribed function values at the knots.
// a[200][4] two dimensional array whose columns are
// the computed spline coefficients
// diff[3] maximum values of differences of values and
// derivatives to right and left of knots.
// com[3] maximum values of coefficients.
//
//
// test of TSpline3 with nonequidistant knots and
// equidistant knots follows.
Double_t hx;
Double_t diff[3];
Double_t a[800], c[4];
Int_t i, j, k, m, n;
Double_t x[200], y[200], z;
Int_t jj, mm;
Int_t mm1, nm1;
Double_t com[3];
printf("1 TEST OF TSpline3 WITH NONEQUIDISTANT KNOTS\n");
n = 5;
x[0] = -3;
x[1] = -1;
x[2] = 0;
x[3] = 3;
x[4] = 4;
y[0] = 7;
y[1] = 11;
y[2] = 26;
y[3] = 56;
y[4] = 29;
m = 2;
mm = m << 1;
mm1 = mm-1;
printf("\n-N = %3d M =%2d\n",n,m);
TSpline3 *spline = new TSpline3("Test",x,y,n);
for (i = 0; i < n; ++i)
spline->GetCoeff(i,hx, a[i],a[i+200],a[i+400],a[i+600]);
delete spline;
for (i = 0; i < mm1; ++i) diff[i] = com[i] = 0;
for (k = 0; k < n; ++k) {
for (i = 0; i < mm; ++i) c[i] = a[k+i*200];
printf(" ---------------------------------------%3d --------------------------------------------\n",k+1);
printf("%12.8f\n",x[k]);
if (k == n-1) {
printf("%16.8f\n",c[0]);
} else {
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
for (i = 0; i < mm1; ++i)
if ((z=TMath::Abs(a[k+i*200])) > com[i]) com[i] = z;
z = x[k+1]-x[k];
for (i = 1; i < mm; ++i)
for (jj = i; jj < mm; ++jj) {
j = mm+i-jj;
c[j-2] = c[j-1]*z+c[j-2];
}
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
for (i = 0; i < mm1; ++i)
if (!(k >= n-2 && i != 0))
if((z = TMath::Abs(c[i]-a[k+1+i*200]))
> diff[i]) diff[i] = z;
}
}
printf(" MAXIMUM ABSOLUTE VALUES OF DIFFERENCES \n");
for (i = 0; i < mm1; ++i) printf("%18.9E",diff[i]);
printf("\n");
printf(" MAXIMUM ABSOLUTE VALUES OF COEFFICIENTS \n");
if (TMath::Abs(c[0]) > com[0])
com[0] = TMath::Abs(c[0]);
for (i = 0; i < mm1; ++i) printf("%16.8f",com[i]);
printf("\n");
m = 2;
for (n = 10; n <= 100; n += 10) {
mm = m << 1;
mm1 = mm-1;
nm1 = n-1;
for (i = 0; i < nm1; i += 2) {
x[i] = i+1;
x[i+1] = i+2;
y[i] = 1;
y[i+1] = 0;
}
if (n % 2 != 0) {
x[n-1] = n;
y[n-1] = 1;
}
printf("\n-N = %3d M =%2d\n",n,m);
spline = new TSpline3("Test",x,y,n);
for (i = 0; i < n; ++i)
spline->GetCoeff(i,hx,a[i],a[i+200],a[i+400],a[i+600]);
delete spline;
for (i = 0; i < mm1; ++i)
diff[i] = com[i] = 0;
for (k = 0; k < n; ++k) {
for (i = 0; i < mm; ++i)
c[i] = a[k+i*200];
if (n < 11) {
printf(" ---------------------------------------%3d --------------------------------------------\n",k+1);
printf("%12.8f\n",x[k]);
if (k == n-1) printf("%16.8f\n",c[0]);
}
if (k == n-1) break;
if (n <= 10) {
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
}
for (i = 0; i < mm1; ++i)
if ((z=TMath::Abs(a[k+i*200])) > com[i])
com[i] = z;
z = x[k+1]-x[k];
for (i = 1; i < mm; ++i)
for (jj = i; jj < mm; ++jj) {
j = mm+i-jj;
c[j-2] = c[j-1]*z+c[j-2];
}
if (n <= 10) {
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
}
for (i = 0; i < mm1; ++i)
if (!(k >= n-2 && i != 0))
if ((z = TMath::Abs(c[i]-a[k+1+i*200]))
> diff[i]) diff[i] = z;
}
printf(" MAXIMUM ABSOLUTE VALUES OF DIFFERENCES \n");
for (i = 0; i < mm1; ++i) printf("%18.9E",diff[i]);
printf("\n");
printf(" MAXIMUM ABSOLUTE VALUES OF COEFFICIENTS \n");
if (TMath::Abs(c[0]) > com[0])
com[0] = TMath::Abs(c[0]);
for (i = 0; i < mm1; ++i) printf("%16.8E",com[i]);
printf("\n");
}
}
//_____________________________________________________________________
Int_t TSpline3::FindX(Double_t x) const
{
// Find X
Int_t klow=0;
//
// If out of boundaries, extrapolate
// It may be badly wrong
if(x<=fXmin) klow=0;
else if(x>=fXmax) klow=fNp-1;
else {
if(fKstep) {
//
// Equidistant knots, use histogramming
klow = TMath::Min(Int_t((x-fXmin)/fDelta),fNp-1);
} else {
Int_t khig=fNp-1, khalf;
//
// Non equidistant knots, binary search
while(khig-klow>1)
if(x>fPoly[khalf=(klow+khig)/2].X())
klow=khalf;
else
khig=khalf;
}
//
// This could be removed, sanity check
if(!(fPoly[klow].X()<=x && x<=fPoly[klow+1].X()))
Error("Eval",
"Binary search failed x(%d) = %f < %f < x(%d) = %f\n",
klow,fPoly[klow].X(),x,fPoly[klow+1].X());
}
return klow;
}
//____________________________________________________________________________
Double_t TSpline3::Eval(Double_t x) const
{
// Eval
Int_t klow=FindX(x);
return fPoly[klow].Eval(x);
}
//____________________________________________________________________________
Double_t TSpline3::Derivative(Double_t x) const
{
// Derivative
Int_t klow=FindX(x);
return fPoly[klow].Derivative(x);
}
//____________________________________________________________________________
void TSpline3::SaveAs(const char *filename) const
{
// write this spline as a C++ function that can be executed without ROOT
// the name of the function is the name of the file up to the "." if any
//open the file
ofstream *f = new ofstream(filename,ios::out
if (f == 0 || gSystem->AccessPathName(filename,kWritePermission)) {
Error("SaveAs","Cannot open file:%s\n",filename);
return;
}
//write the function name and the spline constants
char buffer[512];
Int_t nch = strlen(filename);
sprintf(buffer,"double %s",filename);
char *dot = strstr(buffer,".");
if (dot) *dot = 0;
strcat(buffer,"(double x) {\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," const int fNp = %d, fKstep = %d;\n",fNp,fKstep);
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," const double fDelta = %g, fXmin = %g, fXmax = %g;\n",fDelta,fXmin,fXmax);
nch = strlen(buffer); f->write(buffer,nch);
//write the spline coefficients
//array fX
sprintf(buffer," const double fX[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
Int_t i;
char numb[20];
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].X());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//array fY
sprintf(buffer," const double fY[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].Y());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//array fB
sprintf(buffer," const double fB[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].B());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//array fC
sprintf(buffer," const double fC[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].C());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//array fD
sprintf(buffer," const double fD[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].D());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//generate code for the spline evaluation
sprintf(buffer," int klow=0;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," // If out of boundaries, extrapolate. It may be badly wrong\n");
sprintf(buffer," if(x<=fXmin) klow=0;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," else if(x>=fXmax) klow=fNp-1;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," else {\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," if(fKstep) {\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," // Equidistant knots, use histogramming\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," klow = int((x-fXmin)/fDelta);\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," if (klow < fNp-1) klow = fNp-1;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," } else {\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," int khig=fNp-1, khalf;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," // Non equidistant knots, binary search\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," while(khig-klow>1)\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," if(x>fX[khalf=(klow+khig)/2]) klow=khalf;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," else khig=khalf;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," }\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," }\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," // Evaluate now\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," double dx=x-fX[klow];\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," return (fY[klow]+dx*(fB[klow]+dx*(fC[klow]+dx*fD[klow])));\n");
nch = strlen(buffer); f->write(buffer,nch);
//close file
f->write("}\n",2);
if (f) { f->close(); delete f;}
}
//____________________________________________________________________________
void TSpline3::BuildCoeff()
{
// subroutine cubspl ( tau, c, n, ibcbeg, ibcend )
// from * a practical guide to splines * by c. de boor
// ************************ input ***************************
// n = number of data points. assumed to be .ge. 2.
// (tau(i), c(1,i), i=1,...,n) = abscissae and ordinates of the
// data points. tau is assumed to be strictly increasing.
// ibcbeg, ibcend = boundary condition indicators, and
// c(2,1), c(2,n) = boundary condition information. specifically,
// ibcbeg = 0 means no boundary condition at tau(1) is given.
// in this case, the not-a-knot condition is used, i.e. the
// jump in the third derivative across tau(2) is forced to
// zero, thus the first and the second cubic polynomial pieces
// are made to coincide.)
// ibcbeg = 1 means that the slope at tau(1) is made to equal
// c(2,1), supplied by input.
// ibcbeg = 2 means that the second derivative at tau(1) is
// made to equal c(2,1), supplied by input.
// ibcend = 0, 1, or 2 has analogous meaning concerning the
// boundary condition at tau(n), with the additional infor-
// mation taken from c(2,n).
// *********************** output **************************
// c(j,i), j=1,...,4; i=1,...,l (= n-1) = the polynomial coefficients
// of the cubic interpolating spline with interior knots (or
// joints) tau(2), ..., tau(n-1). precisely, in the interval
// (tau(i), tau(i+1)), the spline f is given by
// f(x) = c(1,i)+h*(c(2,i)+h*(c(3,i)+h*c(4,i)/3.)/2.)
// where h = x - tau(i). the function program *ppvalu* may be
// used to evaluate f or its derivatives from tau,c, l = n-1,
// and k=4.
Int_t i, j, l, m;
Double_t divdf1,divdf3,dtau,g=0;
//***** a tridiagonal linear system for the unknown slopes s(i) of
// f at tau(i), i=1,...,n, is generated and then solved by gauss elim-
// ination, with s(i) ending up in c(2,i), all i.
// c(3,.) and c(4,.) are used initially for temporary storage.
l = fNp-1;
// compute first differences of x sequence and store in C also,
// compute first divided difference of data and store in D.
for (m=1; m<fNp ; ++m) {
fPoly[m].C() = fPoly[m].X() - fPoly[m-1].X();
fPoly[m].D() = (fPoly[m].Y() - fPoly[m-1].Y())/fPoly[m].C();
}
// construct first equation from the boundary condition, of the form
// D[0]*s[0] + C[0]*s[1] = B[0]
if(fBegCond==0) {
if(fNp == 2) {
// no condition at left end and n = 2.
fPoly[0].D() = 1.;
fPoly[0].C() = 1.;
fPoly[0].B() = 2.*fPoly[1].D();
} else {
// not-a-knot condition at left end and n .gt. 2.
fPoly[0].D() = fPoly[2].C();
fPoly[0].C() = fPoly[1].C() + fPoly[2].C();
fPoly[0].B() =((fPoly[1].C()+2.*fPoly[0].C())*fPoly[1].D()*fPoly[2].C()+fPoly[1].C()*fPoly[1].C()*fPoly[2].D())/fPoly[0].C();
}
} else if (fBegCond==1) {
// slope prescribed at left end.
fPoly[0].B() = fValBeg;
fPoly[0].D() = 1.;
fPoly[0].C() = 0.;
} else if (fBegCond==2) {
// second derivative prescribed at left end.
fPoly[0].D() = 2.;
fPoly[0].C() = 1.;
fPoly[0].B() = 3.*fPoly[1].D() - fPoly[1].C()/2.*fValBeg;
}
if(fNp > 2) {
// if there are interior knots, generate the corresp. equations and car-
// ry out the forward pass of gauss elimination, after which the m-th
// equation reads D[m]*s[m] + C[m]*s[m+1] = B[m].
for (m=1; m<l; ++m) {
g = -fPoly[m+1].C()/fPoly[m-1].D();
fPoly[m].B() = g*fPoly[m-1].B() + 3.*(fPoly[m].C()*fPoly[m+1].D()+fPoly[m+1].C()*fPoly[m].D());
fPoly[m].D() = g*fPoly[m-1].C() + 2.*(fPoly[m].C() + fPoly[m+1].C());
}
// construct last equation from the second boundary condition, of the form
// (-g*D[n-2])*s[n-2] + D[n-1]*s[n-1] = B[n-1]
// if slope is prescribed at right end, one can go directly to back-
// substitution, since c array happens to be set up just right for it
// at this point.
if(fEndCond == 0) {
if (fNp > 3 || fBegCond != 0) {
// not-a-knot and n .ge. 3, and either n.gt.3 or also not-a-knot at
// left end point.
g = fPoly[fNp-2].C() + fPoly[fNp-1].C();
fPoly[fNp-1].B() = ((fPoly[fNp-1].C()+2.*g)*fPoly[fNp-1].D()*fPoly[fNp-2].C()
+ fPoly[fNp-1].C()*fPoly[fNp-1].C()*(fPoly[fNp-2].Y()-fPoly[fNp-3].Y())/fPoly[fNp-2].C())/g;
g = -g/fPoly[fNp-2].D();
fPoly[fNp-1].D() = fPoly[fNp-2].C();
} else {
// either (n=3 and not-a-knot also at left) or (n=2 and not not-a-
// knot at left end point).
fPoly[fNp-1].B() = 2.*fPoly[fNp-1].D();
fPoly[fNp-1].D() = 1.;
g = -1./fPoly[fNp-2].D();
}
} else if (fEndCond == 1) {
fPoly[fNp-1].B() = fValEnd;
goto L30;
} else if (fEndCond == 2) {
// second derivative prescribed at right endpoint.
fPoly[fNp-1].B() = 3.*fPoly[fNp-1].D() + fPoly[fNp-1].C()/2.*fValEnd;
fPoly[fNp-1].D() = 2.;
g = -1./fPoly[fNp-2].D();
}
} else {
if(fEndCond == 0) {
if (fBegCond > 0) {
// either (n=3 and not-a-knot also at left) or (n=2 and not not-a-
// knot at left end point).
fPoly[fNp-1].B() = 2.*fPoly[fNp-1].D();
fPoly[fNp-1].D() = 1.;
g = -1./fPoly[fNp-2].D();
} else {
// not-a-knot at right endpoint and at left endpoint and n = 2.
fPoly[fNp-1].B() = fPoly[fNp-1].D();
goto L30;
}
} else if(fEndCond == 1) {
fPoly[fNp-1].B() = fValEnd;
goto L30;
} else if(fEndCond == 2) {
// second derivative prescribed at right endpoint.
fPoly[fNp-1].B() = 3.*fPoly[fNp-1].D() + fPoly[fNp-1].C()/2.*fValEnd;
fPoly[fNp-1].D() = 2.;
g = -1./fPoly[fNp-2].D();
}
}
// complete forward pass of gauss elimination.
fPoly[fNp-1].D() = g*fPoly[fNp-2].C() + fPoly[fNp-1].D();
fPoly[fNp-1].B() = (g*fPoly[fNp-2].B() + fPoly[fNp-1].B())/fPoly[fNp-1].D();
// carry out back substitution
L30: j = l-1;
do {
fPoly[j].B() = (fPoly[j].B() - fPoly[j].C()*fPoly[j+1].B())/fPoly[j].D();
--j;
} while (j>=0);
//****** generate cubic coefficients in each interval, i.e., the deriv.s
// at its left endpoint, from value and slope at its endpoints.
for (i=1; i<fNp; ++i) {
dtau = fPoly[i].C();
divdf1 = (fPoly[i].Y() - fPoly[i-1].Y())/dtau;
divdf3 = fPoly[i-1].B() + fPoly[i].B() - 2.*divdf1;
fPoly[i-1].C() = (divdf1 - fPoly[i-1].B() - divdf3)/dtau;
fPoly[i-1].D() = (divdf3/dtau)/dtau;
}
}
//______________________________________________________________________________
void TSpline3::Streamer(TBuffer &R__b)
{
// Stream an object of class TSpline3.
if (R__b.IsReading()) {
UInt_t R__s, R__c;
Version_t R__v = R__b.ReadVersion(&R__s, &R__c);
if (R__v > 1) {
TSpline3::Class()->ReadBuffer(R__b, this, R__v, R__s, R__c);
return;
}
//====process old versions before automatic schema evolution
TSpline::Streamer(R__b);
if (fNp > 0) {
fPoly = new TSplinePoly3[fNp];
for(Int_t i=0; i<fNp; ++i) {
fPoly[i].Streamer(R__b);
}
}
// R__b >> fPoly;
R__b >> fValBeg;
R__b >> fValEnd;
R__b >> fBegCond;
R__b >> fEndCond;
} else {
TSpline3::Class()->WriteBuffer(R__b,this);
}
}
//////////////////////////////////////////////////////////////////////////
// //
// TSpline5 //
// //
// Class to create quintic natural splines to interpolate knots //
// Arbitrary conditions can be introduced for first and second //
// derivatives using double knots (see BuildCoeff) for more on this. //
// Double knots are automatically introduced at ending points //
// //
//////////////////////////////////////////////////////////////////////////
//____________________________________________________________________________
TSpline5::TSpline5(const char *title,
Double_t x[], Double_t y[], Int_t n,
const char *opt, Double_t b1, Double_t e1,
Double_t b2, Double_t e2) :
TSpline(title,-1, x[0], x[n-1], n, kFALSE)
{
// Quintic natural spline creator given an array of
// arbitrary knots in increasing abscissa order and
// possibly end point conditions
Int_t beg, end;
const char *cb1, *ce1, *cb2, *ce2;
fName="Spline5";
// Check endpoint conditions
BoundaryConditions(opt,beg,end,cb1,ce1,cb2,ce2);
// Create the plynomial terms and fill
// them with node information
fPoly = new TSplinePoly5[fNp];
for (Int_t i=0; i<n; ++i) {
fPoly[i+beg].X() = x[i];
fPoly[i+beg].Y() = y[i];
}
// Set the double knots at boundaries
SetBoundaries(b1,e1,b2,e2,cb1,ce1,cb2,ce2);
// Build the spline coefficients
BuildCoeff();
}
//____________________________________________________________________________
TSpline5::TSpline5(const char *title,
Double_t xmin, Double_t xmax,
Double_t y[], Int_t n,
const char *opt, Double_t b1, Double_t e1,
Double_t b2, Double_t e2) :
TSpline(title,(xmax-xmin)/(n-1), xmin, xmax, n, kTRUE)
{
// Quintic natural spline creator given an array of
// arbitrary function values on equidistant n abscissa
// values from xmin to xmax and possibly end point conditions
Int_t beg, end;
const char *cb1, *ce1, *cb2, *ce2;
fName="Spline5";
// Check endpoint conditions
BoundaryConditions(opt,beg,end,cb1,ce1,cb2,ce2);
// Create the plynomial terms and fill
// them with node information
fPoly = new TSplinePoly5[fNp];
for (Int_t i=0; i<n; ++i) {
fPoly[i+beg].X() = fXmin+i*fDelta;
fPoly[i+beg].Y() = y[i];
}
// Set the double knots at boundaries
SetBoundaries(b1,e1,b2,e2,cb1,ce1,cb2,ce2);
// Build the spline coefficients
BuildCoeff();
}
//____________________________________________________________________________
TSpline5::TSpline5(const char *title,
Double_t x[], const TF1 *func, Int_t n,
const char *opt, Double_t b1, Double_t e1,
Double_t b2, Double_t e2) :
TSpline(title,-1, x[0], x[n-1], n, kFALSE)
{
// Quintic natural spline creator given an array of
// arbitrary abscissas in increasing order and a function
// to interpolate and possibly end point conditions
Int_t beg, end;
const char *cb1, *ce1, *cb2, *ce2;
fName="Spline5";
// Check endpoint conditions
BoundaryConditions(opt,beg,end,cb1,ce1,cb2,ce2);
// Create the plynomial terms and fill
// them with node information
fPoly = new TSplinePoly5[fNp];
for (Int_t i=0; i<n; i++) {
fPoly[i+beg].X() = x[i];
fPoly[i+beg].Y() = ((TF1*)func)->Eval(x[i]);
}
// Set the double knots at boundaries
SetBoundaries(b1,e1,b2,e2,cb1,ce1,cb2,ce2);
// Build the spline coefficients
BuildCoeff();
}
//____________________________________________________________________________
TSpline5::TSpline5(const char *title,
Double_t xmin, Double_t xmax,
const TF1 *func, Int_t n,
const char *opt, Double_t b1, Double_t e1,
Double_t b2, Double_t e2) :
TSpline(title,(xmax-xmin)/(n-1), xmin, xmax, n, kTRUE)
{
// Quintic natural spline creator given a function to be
// evaluated on n equidistand abscissa points between xmin
// and xmax and possibly end point conditions
Int_t beg, end;
const char *cb1, *ce1, *cb2, *ce2;
fName="Spline5";
// Check endpoint conditions
BoundaryConditions(opt,beg,end,cb1,ce1,cb2,ce2);
// Create the plynomial terms and fill
// them with node information
fPoly = new TSplinePoly5[fNp];
for (Int_t i=0; i<n; ++i) {
Double_t x=fXmin+i*fDelta;
fPoly[i+beg].X() = x;
fPoly[i+beg].Y() = ((TF1*)func)->Eval(x);
}
// Set the double knots at boundaries
SetBoundaries(b1,e1,b2,e2,cb1,ce1,cb2,ce2);
// Build the spline coefficients
BuildCoeff();
}
//____________________________________________________________________________
TSpline5::TSpline5(const char *title,
const TGraph *g,
const char *opt, Double_t b1, Double_t e1,
Double_t b2, Double_t e2) :
TSpline(title,-1,0,0,g->GetN(),kFALSE)
{
// Quintic natural spline creator given a TGraph with
// abscissa in increasing order and possibly end
// point conditions
Int_t beg, end;
const char *cb1, *ce1, *cb2, *ce2;
fName="Spline5";
// Check endpoint conditions
BoundaryConditions(opt,beg,end,cb1,ce1,cb2,ce2);
// Create the plynomial terms and fill
// them with node information
fPoly = new TSplinePoly5[fNp];
for (Int_t i=0; i<fNp-beg; ++i) {
Double_t xx, yy;
g->GetPoint(i,xx,yy);
fPoly[i+beg].X()=xx;
fPoly[i+beg].Y()=yy;
}
// Set the double knots at boundaries
SetBoundaries(b1,e1,b2,e2,cb1,ce1,cb2,ce2);
fXmin = fPoly[0].X();
fXmax = fPoly[fNp-1].X();
// Build the spline coefficients
BuildCoeff();
}
//____________________________________________________________________________
void TSpline5::BoundaryConditions(const char *opt,Int_t &beg,Int_t &end,
const char *&cb1,const char *&ce1,
const char *&cb2,const char *&ce2)
{
// Check the boundary conditions and the
// amount of extra double knots needed
cb1=ce1=cb2=ce2=0;
beg=end=0;
if(opt) {
cb1 = strstr(opt,"b1");
ce1 = strstr(opt,"e1");
cb2 = strstr(opt,"b2");
ce2 = strstr(opt,"e2");
if(cb2) {
fNp=fNp+2;
beg=2;
} else if(cb1) {
fNp=fNp+1;
beg=1;
}
if(ce2) {
fNp=fNp+2;
end=2;
} else if(ce1) {
fNp=fNp+1;
end=1;
}
}
}
//____________________________________________________________________________
void TSpline5::SetBoundaries(Double_t b1, Double_t e1, Double_t b2, Double_t e2,
const char *cb1, const char *ce1, const char *cb2,
const char *ce2)
{
// Set the boundary conditions at double/triple knots
if(cb2) {
// Second derivative at the beginning
fPoly[0].X() = fPoly[1].X() = fPoly[2].X();
fPoly[0].Y() = fPoly[2].Y();
fPoly[2].Y()=b2;
// If first derivative not given, we take the finite
// difference from first and second point... not recommended
if(cb1)
fPoly[1].Y()=b1;
else
fPoly[1].Y()=(fPoly[3].Y()-fPoly[0].Y())/(fPoly[3].X()-fPoly[2].X());
} else if(cb1) {
// First derivative at the end
fPoly[0].X() = fPoly[1].X();
fPoly[0].Y() = fPoly[1].Y();
fPoly[1].Y()=b1;
}
if(ce2) {
// Second derivative at the end
fPoly[fNp-1].X() = fPoly[fNp-2].X() = fPoly[fNp-3].X();
fPoly[fNp-1].Y()=e2;
// If first derivative not given, we take the finite
// difference from first and second point... not recommended
if(ce1)
fPoly[fNp-2].Y()=e1;
else
fPoly[fNp-2].Y()=
(fPoly[fNp-3].Y()-fPoly[fNp-4].Y())
/(fPoly[fNp-3].X()-fPoly[fNp-4].X());
} else if(ce1) {
// First derivative at the end
fPoly[fNp-1].X() = fPoly[fNp-2].X();
fPoly[fNp-1].Y()=e1;
}
}
//___________________________________________________________________________
Int_t TSpline5::FindX(Double_t x) const
{
// Find X
Int_t klow=0;
// If out of boundaries, extrapolate
// It may be badly wrong
if(x<=fXmin) klow=0;
else if(x>=fXmax) klow=fNp-1;
else {
if(fKstep) {
// Equidistant knots, use histogramming
klow = TMath::Min(Int_t((x-fXmin)/fDelta),fNp-1);
} else {
Int_t khig=fNp-1, khalf;
// Non equidistant knots, binary search
while(khig-klow>1)
if(x>fPoly[khalf=(klow+khig)/2].X())
klow=khalf;
else
khig=khalf;
}
// This could be removed, sanity check
if(!(fPoly[klow].X()<=x && x<=fPoly[klow+1].X()))
Error("Eval",
"Binary search failed x(%d) = %f < %f < x(%d) = %f\n",
klow,fPoly[klow].X(),x,fPoly[klow+1].X());
}
return klow;
}
//___________________________________________________________________________
Double_t TSpline5::Eval(Double_t x) const
{
// Eval
Int_t klow=FindX(x);
return fPoly[klow].Eval(x);
}
//____________________________________________________________________________
Double_t TSpline5::Derivative(Double_t x) const
{
// Derivative
Int_t klow=FindX(x);
return fPoly[klow].Derivative(x);
}
//____________________________________________________________________________
void TSpline5::SaveAs(const char *filename) const
{
// write this spline as a C++ function that can be executed without ROOT
// the name of the function is the name of the file up to the "." if any
//open the file
ofstream *f = new ofstream(filename,ios::out
if (f == 0 || gSystem->AccessPathName(filename,kWritePermission)) {
Error("SaveAs","Cannot open file:%s\n",filename);
return;
}
//write the function name and the spline constants
char buffer[512];
Int_t nch = strlen(filename);
sprintf(buffer,"double %s",filename);
char *dot = strstr(buffer,".");
if (dot) *dot = 0;
strcat(buffer,"(double x) {\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," const int fNp = %d, fKstep = %d;\n",fNp,fKstep);
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," const double fDelta = %g, fXmin = %g, fXmax = %g;\n",fDelta,fXmin,fXmax);
nch = strlen(buffer); f->write(buffer,nch);
//write the spline coefficients
//array fX
sprintf(buffer," const double fX[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
Int_t i;
char numb[20];
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].X());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//array fY
sprintf(buffer," const double fY[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].Y());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//array fB
sprintf(buffer," const double fB[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].B());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//array fC
sprintf(buffer," const double fC[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].C());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//array fD
sprintf(buffer," const double fD[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].D());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//array fE
sprintf(buffer," const double fE[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].E());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//array fF
sprintf(buffer," const double fF[%d] = {",fNp);
nch = strlen(buffer); f->write(buffer,nch);
buffer[0] = 0;
for (i=0;i<fNp;i++) {
sprintf(numb," %g,",fPoly[i].F());
nch = strlen(numb);
if (i == fNp-1) numb[nch-1]=0;
strcat(buffer,numb);
if (i%5 == 4 || i == fNp-1) {
nch = strlen(buffer); f->write(buffer,nch);
if (i != fNp-1) sprintf(buffer,"\n ");
}
}
sprintf(buffer," };\n");
nch = strlen(buffer); f->write(buffer,nch);
//generate code for the spline evaluation
sprintf(buffer," int klow=0;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," // If out of boundaries, extrapolate. It may be badly wrong\n");
sprintf(buffer," if(x<=fXmin) klow=0;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," else if(x>=fXmax) klow=fNp-1;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," else {\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," if(fKstep) {\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," // Equidistant knots, use histogramming\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," klow = int((x-fXmin)/fDelta);\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," if (klow < fNp-1) klow = fNp-1;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," } else {\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," int khig=fNp-1, khalf;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," // Non equidistant knots, binary search\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," while(khig-klow>1)\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," if(x>fX[khalf=(klow+khig)/2]) klow=khalf;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," else khig=khalf;\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," }\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," }\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," // Evaluate now\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," double dx=x-fX[klow];\n");
nch = strlen(buffer); f->write(buffer,nch);
sprintf(buffer," return (fY[klow]+dx*(fB[klow]+dx*(fC[klow]+dx*(fD[klow]+dx*(fE[klow]+dx*fF[klow])))));\n");
nch = strlen(buffer); f->write(buffer,nch);
//close file
f->write("}\n",2);
if (f) { f->close(); delete f;}
}
//____________________________________________________________________________
void TSpline5::BuildCoeff()
{
// algorithm 600, collected algorithms from acm.
// algorithm appeared in acm-trans. math. software, vol.9, no. 2,
// jun., 1983, p. 258-259.
//
// TSpline5 computes the coefficients of a quintic natural quintic spli
// s(x) with knots x(i) interpolating there to given function values:
// s(x(i)) = y(i) for i = 1,2, ..., n.
// in each interval (x(i),x(i+1)) the spline function s(xx) is a
// polynomial of fifth degree:
// s(xx) = ((((f(i)*p+e(i))*p+d(i))*p+c(i))*p+b(i))*p+y(i) (*)
// = ((((-f(i)*q+e(i+1))*q-d(i+1))*q+c(i+1))*q-b(i+1))*q+y(i+1)
// where p = xx - x(i) and q = x(i+1) - xx.
// (note the first subscript in the second expression.)
// the different polynomials are pieced together so that s(x) and
// its derivatives up to s"" are continuous.
//
// input:
//
// n number of data points, (at least three, i.e. n > 2)
// x(1:n) the strictly increasing or decreasing sequence of
// knots. the spacing must be such that the fifth power
// of x(i+1) - x(i) can be formed without overflow or
// underflow of exponents.
// y(1:n) the prescribed function values at the knots.
//
// output:
//
// b,c,d,e,f the computed spline coefficients as in (*).
// (1:n) specifically
// b(i) = s'(x(i)), c(i) = s"(x(i))/2, d(i) = s"'(x(i))/6,
// e(i) = s""(x(i))/24, f(i) = s""'(x(i))/120.
// f(n) is neither used nor altered. the five arrays
// b,c,d,e,f must always be distinct.
//
// option:
//
// it is possible to specify values for the first and second
// derivatives of the spline function at arbitrarily many knots.
// this is done by relaxing the requirement that the sequence of
// knots be strictly increasing or decreasing. specifically:
//
// if x(j) = x(j+1) then s(x(j)) = y(j) and s'(x(j)) = y(j+1),
// if x(j) = x(j+1) = x(j+2) then in addition s"(x(j)) = y(j+2).
//
// note that s""(x) is discontinuous at a double knot and, in
// addition, s"'(x) is discontinuous at a triple knot. the
// subroutine assigns y(i) to y(i+1) in these cases and also to
// y(i+2) at a triple knot. the representation (*) remains
// valid in each open interval (x(i),x(i+1)). at a double knot,
// x(j) = x(j+1), the output coefficients have the following values:
// y(j) = s(x(j)) = y(j+1)
// b(j) = s'(x(j)) = b(j+1)
// c(j) = s"(x(j))/2 = c(j+1)
// d(j) = s"'(x(j))/6 = d(j+1)
// e(j) = s""(x(j)-0)/24 e(j+1) = s""(x(j)+0)/24
// f(j) = s""'(x(j)-0)/120 f(j+1) = s""'(x(j)+0)/120
// at a triple knot, x(j) = x(j+1) = x(j+2), the output
// coefficients have the following values:
// y(j) = s(x(j)) = y(j+1) = y(j+2)
// b(j) = s'(x(j)) = b(j+1) = b(j+2)
// c(j) = s"(x(j))/2 = c(j+1) = c(j+2)
// d(j) = s"'((x(j)-0)/6 d(j+1) = 0 d(j+2) = s"'(x(j)+0)/6
// e(j) = s""(x(j)-0)/24 e(j+1) = 0 e(j+2) = s""(x(j)+0)/24
// f(j) = s""'(x(j)-0)/120 f(j+1) = 0 f(j+2) = s""'(x(j)+0)/120
Int_t i, m;
Double_t pqqr, p, q, r, s, t, u, v,
b1, p2, p3, q2, q3, r2, pq, pr, qr;
if (fNp <= 2) {
return;
}
// coefficients of a positive definite, pentadiagonal matrix,
// stored in D, E, F from 1 to n-3.
m = fNp-2;
q = fPoly[1].X()-fPoly[0].X();
r = fPoly[2].X()-fPoly[1].X();
q2 = q*q;
r2 = r*r;
qr = q+r;
fPoly[0].D() = fPoly[0].E() = 0;
if (q) fPoly[1].D() = q*6.*q2/(qr*qr);
else fPoly[1].D() = 0;
if (m > 1) {
for (i = 1; i < m; ++i) {
p = q;
q = r;
r = fPoly[i+2].X()-fPoly[i+1].X();
p2 = q2;
q2 = r2;
r2 = r*r;
pq = qr;
qr = q+r;
if (q) {
q3 = q2*q;
pr = p*r;
pqqr = pq*qr;
fPoly[i+1].D() = q3*6./(qr*qr);
fPoly[i].D() += (q+q)*(pr*15.*pr+(p+r)*q
*(pr* 20.+q2*7.)+q2*
((p2+r2)*8.+pr*21.+q2+q2))/(pqqr*pqqr);
fPoly[i-1].D() += q3*6./(pq*pq);
fPoly[i].E() = q2*(p*qr+pq*3.*(qr+r+r))/(pqqr*qr);
fPoly[i-1].E() += q2*(r*pq+qr*3.*(pq+p+p))/(pqqr*pq);
fPoly[i-1].F() = q3/pqqr;
} else
fPoly[i+1].D() = fPoly[i].E() = fPoly[i-1].F() = 0;
}
}
if (r) fPoly[m-1].D() += r*6.*r2/(qr*qr);
// First and second order divided differences of the given function
// values, stored in b from 2 to n and in c from 3 to n
// respectively. care is taken of double and triple knots.
for (i = 1; i < fNp; ++i) {
if (fPoly[i].X() != fPoly[i-1].X()) {
fPoly[i].B() =
(fPoly[i].Y()-fPoly[i-1].Y())/(fPoly[i].X()-fPoly[i-1].X());
} else {
fPoly[i].B() = fPoly[i].Y();
fPoly[i].Y() = fPoly[i-1].Y();
}
}
for (i = 2; i < fNp; ++i) {
if (fPoly[i].X() != fPoly[i-2].X()) {
fPoly[i].C() =
(fPoly[i].B()-fPoly[i-1].B())/(fPoly[i].X()-fPoly[i-2].X());
} else {
fPoly[i].C() = fPoly[i].B()*.5;
fPoly[i].B() = fPoly[i-1].B();
}
}
// Solve the linear system with c(i+2) - c(i+1) as right-hand side. */
if (m > 1) {
p=fPoly[0].C()=fPoly[m-1].E()=fPoly[0].F()
=fPoly[m-2].F()=fPoly[m-1].F()=0;
fPoly[1].C() = fPoly[3].C()-fPoly[2].C();
fPoly[1].D() = 1./fPoly[1].D();
if (m > 2) {
for (i = 2; i < m; ++i) {
q = fPoly[i-1].D()*fPoly[i-1].E();
fPoly[i].D() = 1./(fPoly[i].D()-p*fPoly[i-2].F()-q*fPoly[i-1].E());
fPoly[i].E() -= q*fPoly[i-1].F();
fPoly[i].C() = fPoly[i+2].C()-fPoly[i+1].C()-p*fPoly[i-2].C()
-q*fPoly[i-1].C();
p = fPoly[i-1].D()*fPoly[i-1].F();
}
}
}
fPoly[fNp-2].C() = fPoly[fNp-1].C() = 0;
if (fNp > 3)
for (i=fNp-3; i > 0; --i)
fPoly[i].C() = (fPoly[i].C()-fPoly[i].E()*fPoly[i+1].C()
-fPoly[i].F()*fPoly[i+2].C())*fPoly[i].D();
// Integrate the third derivative of s(x)
m = fNp-1;
q = fPoly[1].X()-fPoly[0].X();
r = fPoly[2].X()-fPoly[1].X();
b1 = fPoly[1].B();
q3 = q*q*q;
qr = q+r;
if (qr) {
v = fPoly[1].C()/qr;
t = v;
} else
v = t = 0;
if (q) fPoly[0].F() = v/q;
else fPoly[0].F() = 0;
for (i = 1; i < m; ++i) {
p = q;
q = r;
if (i != m-1) r = fPoly[i+2].X()-fPoly[i+1].X();
else r = 0;
p3 = q3;
q3 = q*q*q;
pq = qr;
qr = q+r;
s = t;
if (qr) t = (fPoly[i+1].C()-fPoly[i].C())/qr;
else t = 0;
u = v;
v = t-s;
if (pq) {
fPoly[i].F() = fPoly[i-1].F();
if (q) fPoly[i].F() = v/q;
fPoly[i].E() = s*5.;
fPoly[i].D() = (fPoly[i].C()-q*s)*10;
fPoly[i].C() =
fPoly[i].D()*(p-q)+(fPoly[i+1].B()-fPoly[i].B()+(u-fPoly[i].E())*
p3-(v+fPoly[i].E())*q3)/pq;
fPoly[i].B() = (p*(fPoly[i+1].B()-v*q3)+q*(fPoly[i].B()-u*p3))/pq-p
*q*(fPoly[i].D()+fPoly[i].E()*(q-p));
} else {
fPoly[i].C() = fPoly[i-1].C();
fPoly[i].D() = fPoly[i].E() = fPoly[i].F() = 0;
}
}
// End points x(1) and x(n)
p = fPoly[1].X()-fPoly[0].X();
s = fPoly[0].F()*p*p*p;
fPoly[0].E() = fPoly[0].D() = 0;
fPoly[0].C() = fPoly[1].C()-s*10;
fPoly[0].B() = b1-(fPoly[0].C()+s)*p;
q = fPoly[fNp-1].X()-fPoly[fNp-2].X();
t = fPoly[fNp-2].F()*q*q*q;
fPoly[fNp-1].E() = fPoly[fNp-1].D() = 0;
fPoly[fNp-1].C() = fPoly[fNp-2].C()+t*10;
fPoly[fNp-1].B() += (fPoly[fNp-1].C()-t)*q;
}
//___________________________________________________________________________
void TSpline5::Test()
{
// Test method for TSpline5
//
//
// n number of data points.
// m 2*m-1 is order of spline.
// m = 3 always for quintic spline.
// nn,nm1,mm,
// mm1,i,k,
// j,jj temporary integer variables.
// z,p temporary double precision variables.
// x[n] the sequence of knots.
// y[n] the prescribed function values at the knots.
// a[200][6] two dimensional array whose columns are
// the computed spline coefficients
// diff[5] maximum values of differences of values and
// derivatives to right and left of knots.
// com[5] maximum values of coefficients.
//
//
// test of TSpline5 with nonequidistant knots and
// equidistant knots follows.
Double_t hx;
Double_t diff[5];
Double_t a[1200], c[6];
Int_t i, j, k, m, n;
Double_t p, x[200], y[200], z;
Int_t jj, mm, nn;
Int_t mm1, nm1;
Double_t com[5];
printf("1 TEST OF TSpline5 WITH NONEQUIDISTANT KNOTS\n");
n = 5;
x[0] = -3;
x[1] = -1;
x[2] = 0;
x[3] = 3;
x[4] = 4;
y[0] = 7;
y[1] = 11;
y[2] = 26;
y[3] = 56;
y[4] = 29;
m = 3;
mm = m << 1;
mm1 = mm-1;
printf("\n-N = %3d M =%2d\n",n,m);
TSpline5 *spline = new TSpline5("Test",x,y,n);
for (i = 0; i < n; ++i)
spline->GetCoeff(i,hx, a[i],a[i+200],a[i+400],
a[i+600],a[i+800],a[i+1000]);
delete spline;
for (i = 0; i < mm1; ++i) diff[i] = com[i] = 0;
for (k = 0; k < n; ++k) {
for (i = 0; i < mm; ++i) c[i] = a[k+i*200];
printf(" ---------------------------------------%3d --------------------------------------------\n",k+1);
printf("%12.8f\n",x[k]);
if (k == n-1) {
printf("%16.8f\n",c[0]);
} else {
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
for (i = 0; i < mm1; ++i)
if ((z=TMath::Abs(a[k+i*200])) > com[i]) com[i] = z;
z = x[k+1]-x[k];
for (i = 1; i < mm; ++i)
for (jj = i; jj < mm; ++jj) {
j = mm+i-jj;
c[j-2] = c[j-1]*z+c[j-2];
}
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
for (i = 0; i < mm1; ++i)
if (!(k >= n-2 && i != 0))
if((z = TMath::Abs(c[i]-a[k+1+i*200]))
> diff[i]) diff[i] = z;
}
}
printf(" MAXIMUM ABSOLUTE VALUES OF DIFFERENCES \n");
for (i = 0; i < mm1; ++i) printf("%18.9E",diff[i]);
printf("\n");
printf(" MAXIMUM ABSOLUTE VALUES OF COEFFICIENTS \n");
if (TMath::Abs(c[0]) > com[0])
com[0] = TMath::Abs(c[0]);
for (i = 0; i < mm1; ++i) printf("%16.8f",com[i]);
printf("\n");
m = 3;
for (n = 10; n <= 100; n += 10) {
mm = m << 1;
mm1 = mm-1;
nm1 = n-1;
for (i = 0; i < nm1; i += 2) {
x[i] = i+1;
x[i+1] = i+2;
y[i] = 1;
y[i+1] = 0;
}
if (n % 2 != 0) {
x[n-1] = n;
y[n-1] = 1;
}
printf("\n-N = %3d M =%2d\n",n,m);
spline = new TSpline5("Test",x,y,n);
for (i = 0; i < n; ++i)
spline->GetCoeff(i,hx,a[i],a[i+200],a[i+400],
a[i+600],a[i+800],a[i+1000]);
delete spline;
for (i = 0; i < mm1; ++i)
diff[i] = com[i] = 0;
for (k = 0; k < n; ++k) {
for (i = 0; i < mm; ++i)
c[i] = a[k+i*200];
if (n < 11) {
printf(" ---------------------------------------%3d --------------------------------------------\n",k+1);
printf("%12.8f\n",x[k]);
if (k == n-1) printf("%16.8f\n",c[0]);
}
if (k == n-1) break;
if (n <= 10) {
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
}
for (i = 0; i < mm1; ++i)
if ((z=TMath::Abs(a[k+i*200])) > com[i])
com[i] = z;
z = x[k+1]-x[k];
for (i = 1; i < mm; ++i)
for (jj = i; jj < mm; ++jj) {
j = mm+i-jj;
c[j-2] = c[j-1]*z+c[j-2];
}
if (n <= 10) {
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
}
for (i = 0; i < mm1; ++i)
if (!(k >= n-2 && i != 0))
if ((z = TMath::Abs(c[i]-a[k+1+i*200]))
> diff[i]) diff[i] = z;
}
printf(" MAXIMUM ABSOLUTE VALUES OF DIFFERENCES \n");
for (i = 0; i < mm1; ++i) printf("%18.9E",diff[i]);
printf("\n");
printf(" MAXIMUM ABSOLUTE VALUES OF COEFFICIENTS \n");
if (TMath::Abs(c[0]) > com[0])
com[0] = TMath::Abs(c[0]);
for (i = 0; i < mm1; ++i) printf("%16.8E",com[i]);
printf("\n");
}
// Test of TSpline5 with nonequidistant double knots follows
printf("1 TEST OF TSpline5 WITH NONEQUIDISTANT DOUBLE KNOTS\n");
n = 5;
x[0] = -3;
x[1] = -3;
x[2] = -1;
x[3] = -1;
x[4] = 0;
x[5] = 0;
x[6] = 3;
x[7] = 3;
x[8] = 4;
x[9] = 4;
y[0] = 7;
y[1] = 2;
y[2] = 11;
y[3] = 15;
y[4] = 26;
y[5] = 10;
y[6] = 56;
y[7] = -27;
y[8] = 29;
y[9] = -30;
m = 3;
nn = n << 1;
mm = m << 1;
mm1 = mm-1;
printf("-N = %3d M =%2d\n",n,m);
spline = new TSpline5("Test",x,y,nn);
for (i = 0; i < nn; ++i)
spline->GetCoeff(i,hx,a[i],a[i+200],a[i+400],
a[i+600],a[i+800],a[i+1000]);
delete spline;
for (i = 0; i < mm1; ++i)
diff[i] = com[i] = 0;
for (k = 0; k < nn; ++k) {
for (i = 0; i < mm; ++i)
c[i] = a[k+i*200];
printf(" ---------------------------------------%3d --------------------------------------------\n",k+1);
printf("%12.8f\n",x[k]);
if (k == nn-1) {
printf("%16.8f\n",c[0]);
break;
}
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
for (i = 0; i < mm1; ++i)
if ((z=TMath::Abs(a[k+i*200])) > com[i]) com[i] = z;
z = x[k+1]-x[k];
for (i = 1; i < mm; ++i)
for (jj = i; jj < mm; ++jj) {
j = mm+i-jj;
c[j-2] = c[j-1]*z+c[j-2];
}
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
for (i = 0; i < mm1; ++i)
if (!(k >= nn-2 && i != 0))
if ((z = TMath::Abs(c[i]-a[k+1+i*200]))
> diff[i]) diff[i] = z;
}
printf(" MAXIMUM ABSOLUTE VALUES OF DIFFERENCES \n");
for (i = 1; i <= mm1; ++i) {
printf("%18.9E",diff[i-1]);
}
printf("\n");
if (TMath::Abs(c[0]) > com[0])
com[0] = TMath::Abs(c[0]);
printf(" MAXIMUM ABSOLUTE VALUES OF COEFFICIENTS \n");
for (i = 0; i < mm1; ++i) printf("%16.8f",com[i]);
printf("\n");
m = 3;
for (n = 10; n <= 100; n += 10) {
nn = n << 1;
mm = m << 1;
mm1 = mm-1;
p = 0;
for (i = 0; i < n; ++i) {
p += TMath::Abs(TMath::Sin(i+1));
x[(i << 1)] = p;
x[(i << 1)+1] = p;
y[(i << 1)] = TMath::Cos(i+1)-.5;
y[(i << 1)+1] = TMath::Cos((i << 1)+2)-.5;
}
printf("-N = %3d M =%2d\n",n,m);
spline = new TSpline5("Test",x,y,nn);
for (i = 0; i < nn; ++i)
spline->GetCoeff(i,hx,a[i],a[i+200],a[i+400],
a[i+600],a[i+800],a[i+1000]);
delete spline;
for (i = 0; i < mm1; ++i)
diff[i] = com[i] = 0;
for (k = 0; k < nn; ++k) {
for (i = 0; i < mm; ++i)
c[i] = a[k+i*200];
if (n < 11) {
printf(" ---------------------------------------%3d --------------------------------------------\n",k+1);
printf("%12.8f\n",x[k]);
if (k == nn-1) printf("%16.8f\n",c[0]);
}
if (k == nn-1) break;
if (n <= 10) {
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
}
for (i = 0; i < mm1; ++i)
if ((z=TMath::Abs(a[k+i*200])) > com[i]) com[i] = z;
z = x[k+1]-x[k];
for (i = 1; i < mm; ++i) {
for (jj = i; jj < mm; ++jj) {
j = mm+i-jj;
c[j-2] = c[j-1]*z+c[j-2];
}
}
if (n <= 10) {
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
}
for (i = 0; i < mm1; ++i)
if (!(k >= nn-2 && i != 0))
if ((z = TMath::Abs(c[i]-a[k+1+i*200]))
> diff[i]) diff[i] = z;
}
printf(" MAXIMUM ABSOLUTE VALUES OF DIFFERENCES \n");
for (i = 0; i < mm1; ++i) printf("%18.9E",diff[i]);
printf("\n");
printf(" MAXIMUM ABSOLUTE VALUES OF COEFFICIENTS \n");
if (TMath::Abs(c[0]) > com[0])
com[0] = TMath::Abs(c[0]);
for (i = 0; i < mm1; ++i) printf("%18.9E",com[i]);
printf("\n");
}
// test of TSpline5 with nonequidistant knots, one double knot,
// one triple knot, follows.
printf("1 TEST OF TSpline5 WITH NONEQUIDISTANT KNOTS,\n");
printf(" ONE DOUBLE, ONE TRIPLE KNOT\n");
n = 8;
x[0] = -3;
x[1] = -1;
x[2] = -1;
x[3] = 0;
x[4] = 3;
x[5] = 3;
x[6] = 3;
x[7] = 4;
y[0] = 7;
y[1] = 11;
y[2] = 15;
y[3] = 26;
y[4] = 56;
y[5] = -30;
y[6] = -7;
y[7] = 29;
m = 3;
mm = m << 1;
mm1 = mm-1;
printf("-N = %3d M =%2d\n",n,m);
spline=new TSpline5("Test",x,y,n);
for (i = 0; i < n; ++i)
spline->GetCoeff(i,hx,a[i],a[i+200],a[i+400],
a[i+600],a[i+800],a[i+1000]);
delete spline;
for (i = 0; i < mm1; ++i)
diff[i] = com[i] = 0;
for (k = 0; k < n; ++k) {
for (i = 0; i < mm; ++i)
c[i] = a[k+i*200];
printf(" ---------------------------------------%3d --------------------------------------------\n",k+1);
printf("%12.8f\n",x[k]);
if (k == n-1) {
printf("%16.8f\n",c[0]);
break;
}
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
for (i = 0; i < mm1; ++i)
if ((z=TMath::Abs(a[k+i*200])) > com[i]) com[i] = z;
z = x[k+1]-x[k];
for (i = 1; i < mm; ++i)
for (jj = i; jj < mm; ++jj) {
j = mm+i-jj;
c[j-2] = c[j-1]*z+c[j-2];
}
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
for (i = 0; i < mm1; ++i)
if (!(k >= n-2 && i != 0))
if ((z = TMath::Abs(c[i]-a[k+1+i*200]))
> diff[i]) diff[i] = z;
}
printf(" MAXIMUM ABSOLUTE VALUES OF DIFFERENCES \n");
for (i = 0; i < mm1; ++i) printf("%18.9E",diff[i]);
printf("\n");
printf(" MAXIMUM ABSOLUTE VALUES OF COEFFICIENTS \n");
if (TMath::Abs(c[0]) > com[0])
com[0] = TMath::Abs(c[0]);
for (i = 0; i < mm1; ++i) printf("%16.8f",com[i]);
printf("\n");
// Test of TSpline5 with nonequidistant knots, two double knots,
// one triple knot,follows.
printf("1 TEST OF TSpline5 WITH NONEQUIDISTANT KNOTS,\n");
printf(" TWO DOUBLE, ONE TRIPLE KNOT\n");
n = 10;
x[0] = 0;
x[1] = 2;
x[2] = 2;
x[3] = 3;
x[4] = 3;
x[5] = 3;
x[6] = 5;
x[7] = 8;
x[8] = 9;
x[9] = 9;
y[0] = 163;
y[1] = 237;
y[2] = -127;
y[3] = 119;
y[4] = -65;
y[5] = 192;
y[6] = 293;
y[7] = 326;
y[8] = 0;
y[9] = -414;
m = 3;
mm = m << 1;
mm1 = mm-1;
printf("-N = %3d M =%2d\n",n,m);
spline = new TSpline5("Test",x,y,n);
for (i = 0; i < n; ++i)
spline->GetCoeff(i,hx,a[i],a[i+200],a[i+400],
a[i+600],a[i+800],a[i+1000]);
delete spline;
for (i = 0; i < mm1; ++i)
diff[i] = com[i] = 0;
for (k = 0; k < n; ++k) {
for (i = 0; i < mm; ++i)
c[i] = a[k+i*200];
printf(" ---------------------------------------%3d --------------------------------------------\n",k+1);
printf("%12.8f\n",x[k]);
if (k == n-1) {
printf("%16.8f\n",c[0]);
break;
}
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
for (i = 0; i < mm1; ++i)
if ((z=TMath::Abs(a[k+i*200])) > com[i]) com[i] = z;
z = x[k+1]-x[k];
for (i = 1; i < mm; ++i)
for (jj = i; jj < mm; ++jj) {
j = mm+i-jj;
c[j-2] = c[j-1]*z+c[j-2];
}
for (i = 0; i < mm; ++i) printf("%16.8f",c[i]);
printf("\n");
for (i = 0; i < mm1; ++i)
if (!(k >= n-2 && i != 0))
if((z = TMath::Abs(c[i]-a[k+1+i*200]))
> diff[i]) diff[i] = z;
}
printf(" MAXIMUM ABSOLUTE VALUES OF DIFFERENCES \n");
for (i = 0; i < mm1; ++i) printf("%18.9E",diff[i]);
printf("\n");
printf(" MAXIMUM ABSOLUTE VALUES OF COEFFICIENTS \n");
if (TMath::Abs(c[0]) > com[0])
com[0] = TMath::Abs(c[0]);
for (i = 0; i < mm1; ++i) printf("%16.8f",com[i]);
printf("\n");
}
//______________________________________________________________________________
void TSpline5::Streamer(TBuffer &R__b)
{
// Stream an object of class TSpline5.
if (R__b.IsReading()) {
UInt_t R__s, R__c;
Version_t R__v = R__b.ReadVersion(&R__s, &R__c);
if (R__v > 1) {
TSpline5::Class()->ReadBuffer(R__b, this, R__v, R__s, R__c);
return;
}
//====process old versions before automatic schema evolution
TSpline::Streamer(R__b);
if (fNp > 0) {
fPoly = new TSplinePoly5[fNp];
for(Int_t i=0; i<fNp; ++i) {
fPoly[i].Streamer(R__b);
}
}
// R__b >> fPoly;
} else {
TSpline5::Class()->WriteBuffer(R__b,this);
}
}
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