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timeonaxis.C File Reference

Detailed Description

View in nbviewer Open in SWAN This macro illustrates the use of the time mode on the axis with different time intervals and time formats.

Through all this script, the time is expressed in UTC. some information about this format (and others like GPS) may be found at http://tycho.usno.navy.mil/systime.html or http://www.topology.org/sci/time.html

The start time is : almost NOW (the time at which the script is executed) actually, the nearest preceding hour beginning. The time is in general expressed in UTC time with the C time() function This will obviously most of the time not be the time displayed on your watch since it is universal time. See the C time functions for converting this time into more useful structures.

#include <time.h>
TCanvas *timeonaxis()
time_t script_time;
script_time = time(0);
script_time = 3600*(int)(script_time/3600);
// The time offset is the one that will be used by all graphs.
// If one changes it, it will be changed even on the graphs already defined
TCanvas *ct = new TCanvas("ct","Time on axis",10,10,700,900);
int i;
//### Build a signal : noisy damped sine
// Time interval : 30 minutes
float noise;
TH1F *ht = new TH1F("ht","Love at first sight",3000,0.,2000.);
for (i=1;i<3000;i++) {
noise = gRandom->Gaus(0,120);
if (i>700) {
noise += 1000*sin((i-700)*6.28/30)*exp((double)(700-i)/300);
// Sets time on the X axis
// The time used is the one set as time offset added to the value
// of the axis. This is converted into day/month/year hour:min:sec and
// a reasonable tick interval value is chosen.
//### Build a simple graph beginning at a different time
// Time interval : 5 seconds
float x[100], t[100];
for (i=0;i<100;i++) {
x[i] = sin(i*4*3.1415926/50)*exp(-(double)i/20);
t[i] = 6000+(double)i/20;
TGraph *gt = new TGraph(100,t,x);
// Sets time on the X axis
//### Build a second simple graph for a very long time interval
// Time interval : a few years
float x2[10], t2[10];
for (i=0;i<10;i++) {
x2[i] = gRandom->Gaus(500,100)*i;
t2[i] = i*365*86400;
TGraph *gt2 = new TGraph(10,t2,x2);
gt2->SetTitle("Number of monkeys on the moon");
// Sets time on the X axis
// One can choose a different time format than the one chosen by default
// The time format is the same as the one of the C strftime() function
// It's a string containing the following formats :
// for date :
// %a abbreviated weekday name
// %b abbreviated month name
// %d day of the month (01-31)
// %m month (01-12)
// %y year without century
// %Y year with century
// for time :
// %H hour (24-hour clock)
// %I hour (12-hour clock)
// %p local equivalent of AM or PM
// %M minute (00-59)
// %S seconds (00-61)
// %% %
// The other characters are output as is.
gt2->GetXaxis()->SetTimeFormat("y. %Y %F2000-01-01 00:00:00");
return ct;
static const double x2[5]
double sin(double)
double exp(double)
R__EXTERN TRandom * gRandom
Definition TRandom.h:62
R__EXTERN TStyle * gStyle
Definition TStyle.h:412
#define gPad
virtual void SetLabelSize(Float_t size=0.04)
Set size of axis labels.
Definition TAttAxis.cxx:203
virtual void SetLineWidth(Width_t lwidth)
Set the line width.
Definition TAttLine.h:43
virtual void SetLineColor(Color_t lcolor)
Set the line color.
Definition TAttLine.h:40
virtual void SetMarkerColor(Color_t mcolor=1)
Set the marker color.
Definition TAttMarker.h:38
virtual void SetMarkerStyle(Style_t mstyle=1)
Set the marker style.
Definition TAttMarker.h:40
virtual void SetMarkerSize(Size_t msize=1)
Set the marker size.
Definition TAttMarker.h:41
virtual void SetTimeDisplay(Int_t value)
Definition TAxis.h:161
virtual void SetTimeFormat(const char *format="")
Change the format used for time plotting.
Definition TAxis.cxx:1020
The Canvas class.
Definition TCanvas.h:23
TVirtualPad * cd(Int_t subpadnumber=0) override
Set current canvas & pad.
Definition TCanvas.cxx:708
A TGraph is an object made of two arrays X and Y with npoints each.
Definition TGraph.h:41
virtual void SetTitle(const char *title="")
Change (i.e.
Definition TGraph.cxx:2339
virtual void Draw(Option_t *chopt="")
Draw this graph with its current attributes.
Definition TGraph.cxx:769
TAxis * GetXaxis() const
Get x axis of the graph.
Definition TGraph.cxx:1640
1-D histogram with a float per channel (see TH1 documentation)}
Definition TH1.h:575
TAxis * GetXaxis()
Get the behaviour adopted by the object about the statoverflows. See EStatOverflows for more informat...
Definition TH1.h:320
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:9062
virtual void Draw(Option_t *option="")
Draw this histogram with options.
Definition TH1.cxx:3073
void Divide(Int_t nx=1, Int_t ny=1, Float_t xmargin=0.01, Float_t ymargin=0.01, Int_t color=0) override
Automatic pad generation by division.
Definition TPad.cxx:1177
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:274
void SetTimeOffset(Double_t toffset)
Change the time offset for time plotting.
Definition TStyle.cxx:1800
void SetTitleH(Float_t h=0)
Definition TStyle.h:399
Double_t x[n]
Definition legend1.C:17
Damir Buskulic

Definition in file timeonaxis.C.