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Reference Guide
timeonaxis.C
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1 /// \file
2 /// \ingroup tutorial_graphs
3 /// \notebook -js
4 /// This macro illustrates the use of the time mode on the axis
5 /// with different time intervals and time formats.
6 /// Through all this script, the time is expressed in UTC. some
7 /// information about this format (and others like GPS) may be found at
8 /// <a href="http://tycho.usno.navy.mil/systime.html">http://tycho.usno.navy.mil/systime.html</a>
9 /// or
10 /// <a href="http://www.topology.org/sci/time.html">http://www.topology.org/sci/time.html</a>
11 ///
12 /// The start time is : almost NOW (the time at which the script is executed)
13 /// actually, the nearest preceding hour beginning.
14 /// The time is in general expressed in UTC time with the C time() function
15 /// This will obviously most of the time not be the time displayed on your watch
16 /// since it is universal time. See the C time functions for converting this time
17 /// into more useful structures.
18 ///
19 /// \macro_image
20 /// \macro_code
21 ///
22 /// \author Damir Buskulic
23 
24 #include <time.h>
25 
26 TCanvas *timeonaxis()
27 {
28 
29  time_t script_time;
30  script_time = time(0);
31  script_time = 3600*(int)(script_time/3600);
32 
33 // The time offset is the one that will be used by all graphs.
34 // If one changes it, it will be changed even on the graphs already defined
35  gStyle->SetTimeOffset(script_time);
36 
37  TCanvas *ct = new TCanvas("ct","Time on axis",10,10,700,900);
38  ct->Divide(1,3);
39 
40  int i;
41 
42 //### Build a signal : noisy damped sine
43 // Time interval : 30 minutes
44 
45  gStyle->SetTitleH(0.08);
46  float noise;
47  TH1F *ht = new TH1F("ht","Love at first sight",3000,0.,2000.);
48  for (i=1;i<3000;i++) {
49  noise = gRandom->Gaus(0,120);
50  if (i>700) {
51  noise += 1000*sin((i-700)*6.28/30)*exp((double)(700-i)/300);
52  }
53  ht->SetBinContent(i,noise);
54  }
55  ct->cd(1);
56  ht->SetLineColor(2);
57  ht->GetXaxis()->SetLabelSize(0.05);
58  ht->Draw();
59 // Sets time on the X axis
60 // The time used is the one set as time offset added to the value
61 // of the axis. This is converted into day/month/year hour:min:sec and
62 // a reasonable tick interval value is chosen.
63  ht->GetXaxis()->SetTimeDisplay(1);
64 
65 //### Build a simple graph beginning at a different time
66 // Time interval : 5 seconds
67 
68  float x[100], t[100];
69  for (i=0;i<100;i++) {
70  x[i] = sin(i*4*3.1415926/50)*exp(-(double)i/20);
71  t[i] = 6000+(double)i/20;
72  }
73  TGraph *gt = new TGraph(100,t,x);
74  gt->SetTitle("Politics");
75  ct->cd(2);
76  gt->SetLineColor(5);
77  gt->SetLineWidth(2);
78  gt->Draw("AL");
79  gt->GetXaxis()->SetLabelSize(0.05);
80 // Sets time on the X axis
81  gt->GetXaxis()->SetTimeDisplay(1);
82  gPad->Modified();
83 
84 //### Build a second simple graph for a very long time interval
85 // Time interval : a few years
86 
87  float x2[10], t2[10];
88  for (i=0;i<10;i++) {
89  x2[i] = gRandom->Gaus(500,100)*i;
90  t2[i] = i*365*86400;
91  }
92  TGraph *gt2 = new TGraph(10,t2,x2);
93  gt2->SetTitle("Number of monkeys on the moon");
94  ct->cd(3);
95  gt2->SetMarkerColor(4);
96  gt2->SetMarkerStyle(29);
97  gt2->SetMarkerSize(1.3);
98  gt2->Draw("AP");
99  gt2->GetXaxis()->SetLabelSize(0.05);
100 // Sets time on the X axis
101  gt2->GetXaxis()->SetTimeDisplay(1);
102 //
103 // One can choose a different time format than the one chosen by default
104 // The time format is the same as the one of the C strftime() function
105 // It's a string containing the following formats :
106 //
107 // for date :
108 // %a abbreviated weekday name
109 // %b abbreviated month name
110 // %d day of the month (01-31)
111 // %m month (01-12)
112 // %y year without century
113 // %Y year with century
114 //
115 // for time :
116 // %H hour (24-hour clock)
117 // %I hour (12-hour clock)
118 // %p local equivalent of AM or PM
119 // %M minute (00-59)
120 // %S seconds (00-61)
121 // %% %
122 // The other characters are output as is.
123 
124  gt2->GetXaxis()->SetTimeFormat("y. %Y %F2000-01-01 00:00:00");
125  gPad->Modified();
126  return ct;
127 }
virtual void SetLineWidth(Width_t lwidth)
Set the line width.
Definition: TAttLine.h:43
virtual void SetTimeFormat(const char *format="")
Change the format used for time plotting.
Definition: TAxis.cxx:1002
virtual Double_t Gaus(Double_t mean=0, Double_t sigma=1)
Samples a random number from the standard Normal (Gaussian) Distribution with the given mean and sigm...
Definition: TRandom.cxx:256
R__EXTERN TStyle * gStyle
Definition: TStyle.h:402
THist< 1, float, THistStatContent, THistStatUncertainty > TH1F
Definition: THist.hxx:285
TVirtualPad * cd(Int_t subpadnumber=0)
Set current canvas & pad.
Definition: TCanvas.cxx:688
1-D histogram with a float per channel (see TH1 documentation)}
Definition: TH1.h:567
virtual void SetTitle(const char *title="")
Set graph title.
Definition: TGraph.cxx:2208
void SetTimeOffset(Double_t toffset)
Change the time offset for time plotting.
Definition: TStyle.cxx:1477
virtual void Draw(Option_t *chopt="")
Draw this graph with its current attributes.
Definition: TGraph.cxx:745
static const double x2[5]
Double_t x[n]
Definition: legend1.C:17
virtual void SetMarkerColor(Color_t mcolor=1)
Set the marker color.
Definition: TAttMarker.h:38
double sin(double)
virtual void SetTimeDisplay(Int_t value)
Definition: TAxis.h:161
virtual void SetLineColor(Color_t lcolor)
Set the line color.
Definition: TAttLine.h:40
virtual void Draw(Option_t *option="")
Draw this histogram with options.
Definition: TH1.cxx:2969
virtual void SetBinContent(Int_t bin, Double_t content)
Set bin content see convention for numbering bins in TH1::GetBin In case the bin number is greater th...
Definition: TH1.cxx:8477
virtual void SetMarkerStyle(Style_t mstyle=1)
Set the marker style.
Definition: TAttMarker.h:40
R__EXTERN TRandom * gRandom
Definition: TRandom.h:62
void SetTitleH(Float_t h=0)
Definition: TStyle.h:389
virtual void SetLabelSize(Float_t size=0.04)
Set size of axis labels The size is expressed in per cent of the pad width.
Definition: TAttAxis.cxx:204
virtual void SetMarkerSize(Size_t msize=1)
Set the marker size.
Definition: TAttMarker.h:41
TAxis * GetXaxis() const
Get x axis of the graph.
Definition: TGraph.cxx:1592
The Canvas class.
Definition: TCanvas.h:31
virtual void Divide(Int_t nx=1, Int_t ny=1, Float_t xmargin=0.01, Float_t ymargin=0.01, Int_t color=0)
Automatic pad generation by division.
Definition: TPad.cxx:1153
A Graph is a graphics object made of two arrays X and Y with npoints each.
Definition: TGraph.h:41
#define gPad
Definition: TVirtualPad.h:285
double exp(double)
TAxis * GetXaxis()
Get the behaviour adopted by the object about the statoverflows. See EStatOverflows for more informat...
Definition: TH1.h:315