void th2polyUSA()
{
Int_t i, bin;
const Int_t nx = 48;
char *states [nx] = {
"alabama", "arizona", "arkansas", "california",
"colorado", "connecticut", "delaware", "florida",
"georgia", "idaho", "illinois", "indiana",
"iowa", "kansas", "kentucky", "louisiana",
"maine", "maryland", "massachusetts", "michigan",
"minnesota", "mississippi", "missouri", "montana",
"nebraska", "nevada", "new_hampshire", "new_jersey",
"new_mexico", "new_york", "north_carolina", "north_dakota",
"ohio", "oklahoma", "oregon", "pennsylvania",
"rhode_island", "south_carolina", "south_dakota", "tennessee",
"texas", "utah", "vermont", "virginia",
"washington", "west_virginia", "wisconsin", "wyoming"
};
Float_t pop[nx] = {
4708708, 6595778, 2889450, 36961664, 5024748, 3518288, 885122, 18537969,
9829211, 1545801, 12910409, 6423113, 3007856, 2818747, 4314113, 4492076,
1318301, 5699478, 6593587, 9969727, 5266214, 2951996, 5987580, 974989,
1796619, 2643085, 1324575, 8707739, 2009671, 19541453, 9380884, 646844,
11542645, 3687050, 3825657, 12604767, 1053209, 4561242, 812383, 6296254,
24782302, 2784572, 621760, 7882590, 6664195, 1819777, 5654774, 544270
};
gStyle->SetCanvasPreferGL(true);
TCanvas *usa = new TCanvas("USA", "USA");
usa->ToggleEventStatus();
Double_t lon1 = -130;
Double_t lon2 = -65;
Double_t lat1 = 24;
Double_t lat2 = 50;
TH2Poly *p = new TH2Poly("USA","USA Population",lon1,lon2,lat1,lat2);
TFile *f;
f = TFile::Open("http://root.cern.ch/files/usa.root");
// Define the TH2Poly bins.
TMultiGraph *mg;
TKey *key;
TIter nextkey(gDirectory->GetListOfKeys());
while (key = (TKey*)nextkey()) {
obj = key->ReadObj();
if (obj->InheritsFrom("TMultiGraph")) {
mg = (TMultiGraph*)obj;
bin = p->AddBin(mg);
}
}
// Fill TH2Poly.
for (i=0; i<nx; i++) p->Fill(states[i], pop[i]);
gStyle->SetOptStat(11);
gStyle->SetPalette(1);
p->Draw("gllego");
}
void th2polyHoneycomb(){
gStyle->SetCanvasPreferGL(true);
TH2Poly *hc = new TH2Poly();
hc->Honeycomb(0,0,.1,25,25);
TRandom ran;
for (int i = 0; i<30000; i++) {
hc->Fill(ran.Gaus(2.,1), ran.Gaus(2.,1));
}
hc->Draw("gllego");
}
void th2polyEurope(Int_t npoints=500000)
{
Int_t i,j;
Double_t lon1 = -25;
Double_t lon2 = 35;
Double_t lat1 = 34;
Double_t lat2 = 72;
Double_t R = (lat2-lat1)/(lon2-lon1);
Int_t W = 800;
Int_t H = (Int_t)(R*800);
gStyle->SetStatX(0.28);
gStyle->SetStatY(0.45);
gStyle->SetStatW(0.15);
// Canvas used to draw TH2Poly (the map)
TCanvas *ce = new TCanvas("ce", "ce",0,0,W,H);
ce->ToggleEventStatus();
ce->SetGridx();
ce->SetGridy();
// Real surfaces taken from Wikipedia.
const Int_t nx = 36;
// see http://en.wikipedia.org/wiki/Area_and_population_of_European_countries
const char *countries[nx] = {
"france", "spain", "sweden", "germany", "finland",
"norway", "poland", "italy", "yugoslavia", "united_kingdom",
"romania", "belarus","greece", "czechoslovakia","bulgaria",
"iceland", "hungary","portugal","austria", "ireland",
"lithuania", "latvia", "estonia", "denmark", "netherlands",
"switzerland","moldova","belgium", "albania", "cyprus",
"luxembourg", "andorra","malta", "liechtenstein", "san_marino", "monaco" };
Float_t surfaces[nx] = {
547030, 505580, 449964, 357021, 338145,
324220, 312685, 301230, 255438, 244820,
237500, 207600, 131940, 127711, 110910,
103000, 93030, 89242, 83870, 70280,
65200, 64589, 45226, 43094, 41526,
41290, 33843, 30528, 28748, 9250,
2586, 468, 316, 160, 61, 2};
TH1F *h = new TH1F("h","Countries surfaces (in km^{2})",3,0,3);
for (i=0; i<nx; i++) h->Fill(countries[i], surfaces[i]);
h->LabelsDeflate();
TFile::SetCacheFileDir(".");
TFile *f;
f = TFile::Open("http://root.cern.ch/files/europe.root","cacheread");
if (!f) {
printf("Cannot access europe.root. Is internet working ?\n");
return;
}
TH2Poly *p = new TH2Poly(
"Europe",
"Europe (bin contents are normalized to the surfaces in km^{2})",
lon1,lon2,lat1,lat2);
p->GetXaxis()->SetNdivisions(520);
p->GetXaxis()->SetTitle("longitude");
p->GetYaxis()->SetTitle("latitude");
p->SetContour(100);
TMultiGraph *mg;
TKey *key;
TIter nextkey(gDirectory->GetListOfKeys());
while ((key = (TKey*)nextkey())) {
TObject *obj = key->ReadObj();
if (obj->InheritsFrom("TMultiGraph")) {
mg = (TMultiGraph*)obj;
p->AddBin(mg);
}
}
TRandom r;
Double_t longitude, latitude;
Double_t x, y, pi4 = TMath::Pi()/4, alpha = TMath::Pi()/360;
gBenchmark->Start("Partitioning");
p->ChangePartition(100, 100);
gBenchmark->Show("Partitioning");
// Fill TH2Poly according to a Mercator projection.
gBenchmark->Start("Filling");
for (i=0; i<npoints; i++) {
longitude = r.Uniform(lon1,lon2);
latitude = r.Uniform(lat1,lat2);
x = longitude;
y = 38*TMath::Log(TMath::Tan(pi4+alpha*latitude));
p->Fill(x,y);
}
gBenchmark->Show("Filling");
Int_t nbins = p->GetNumberOfBins();
Double_t maximum = p->GetMaximum();
// h2 contains the surfaces computed from TH2Poly.
TH1F *h2 = (TH1F *)h->Clone("h2");
h2->Reset();
for (j=0; j<nx; j++) {
for (i=0; i<nbins; i++) {
if (strstr(countries[j],p->GetBinName(i+1))) {
h2->Fill(countries[j],p->GetBinContent(i+1));
h2->SetBinError(j, p->GetBinError(i+1));
}
}
}
// Normalize the TH2Poly bin contents to the real surfaces.
Double_t scale = surfaces[0]/maximum;
for (i=0; i<nbins; i++) p->SetBinContent(i+1, scale*p->GetBinContent(i+1));
gStyle->SetOptStat(1111);
p->Draw("COLZ");
TCanvas *c1 = new TCanvas("c1", "c1",W+10,0,W-20,H);
c1->SetRightMargin(0.047);
scale = h->GetMaximum()/h2->GetMaximum();
h->SetStats(0);
h->SetLineColor(kRed-3);
h->SetLineWidth(2);
h->SetMarkerStyle(20);
h->SetMarkerColor(kBlue);
h->SetMarkerSize(0.8);
h->Draw("LP");
h->GetXaxis()->SetLabelFont(42);
h->GetXaxis()->SetLabelSize(0.03);
h->GetYaxis()->SetLabelFont(42);
h2->Scale(scale);
Double_t scale2=TMath::Sqrt(scale);
for (i=0; i<nx; i++) h2->SetBinError(i+1, scale2*h2->GetBinError(i+1));
h2->Draw("E SAME");
h2->SetMarkerStyle(20);
h2->SetMarkerSize(0.8);
TLegend *leg = new TLegend(0.5,0.67,0.92,0.8,NULL,"NDC");
leg->SetTextFont(42);
leg->SetTextSize(0.025);
leg->AddEntry(h,"Real countries surfaces from Wikipedia (in km^{2})","lp");
leg->AddEntry(h2,"Countries surfaces from TH2Poly (with errors)","lp");
leg->Draw();
leg->Draw();
Double_t wikiSum = h->Integral();
Double_t polySum = h2->Integral();
Double_t error = TMath::Abs(wikiSum-polySum)/wikiSum;
printf("THPoly Europe surface estimation error wrt wikipedia = %f per cent when using %d points\n",100*error,npoints);
}