// This TJD date indication was used by the Vela and Batse missions in
// view of Gamma Ray Burst investigations.
//
-// The Julian Epoch (JE) indicates the fractional elapsed year count since
-// midnight (UT) on 01-jan at the start of the Gregorian year count.
-// A year is defined to be 365.25 days, so the integer part of JE corresponds
-// to the usual Gregorian year count.
-// So, 01-jan-1965 00:00:00 UT corresponds to JE=1965.0
+// The Julian Epoch (JE) indicates the fractional elapsed Julian year count
+// since the start of the Gregorian year count.
+// A Julian year is defined to be 365.25 days and starts at 01-jan 12:00:00 UT.
+// As such, the integer part of JE corresponds to the usual Gregorian year count,
+// apart from 01-jan before 12:00:00 UT.
+// So, 01-jan-1965 12:00:00 UT corresponds to JE=1965.0
+//
+// The Besselian Epoch (BE) indicates the fractional elapsed Besselian year count
+// since the start of the Gregorian year count.
+// A Besselian (or tropical) year is defined to be 365.242198781 days.
+// The date 31-dec-1949 22:09:46.862 UT corresponds to BE=1950.0
+//
+// The Besselian and Julian epochs are used in astronomical catalogs
+// to denote values of time varying observables like e.g. right ascension.
//
// Because of the fact that the Julian date indicators are all w.r.t. UT
// they provide an absolute timescale irrespective of timezone or daylight
// saving time (DST).
//
-// This AliTimestamp facility allows for nanosecond precision.
-// However, when the fractional JD, MJD and TJD counts are used instead
+// In view of astronomical observations and positioning it is convenient
+// to have also a UT equivalent related to stellar meridian transitions.
+// This is achieved by the Greenwich Sidereal Time (GST).
+// The GST is defined as the right ascension of the objects passing
+// the Greenwich meridian at 00:00:00 UT.
+// Due to the rotation of the Earth around the Sun, a sidereal day
+// lasts 86164.09 seconds (23h 56m 04.09s) compared to the mean solar
+// day of 86400 seconds (24h).
+// Furthermore, precession of the earth's spin axis results in the fact
+// that the zero point of right ascension (vernal equinox) gradually
+// moves along the celestial equator.
+// In addition, tidal friction and ocean and atmospheric effects will
+// induce seasonal variations in the earth's spin rate and polar motion
+// of the earth's spin axis.
+// Taking the above effects into account leads to what is called
+// the Greenwich Mean Sidereal Time (GMST).
+// In case also the nutation of the earth's spin axis is taken into
+// account we speak of the Greenwich Apparent Sidereal Time (GAST).
+//
+// This AliTimestamp facility allows for picosecond precision, in view
+// of time of flight analyses for particle physics experiments.
+// For normal date/time indication the standard nanosecond precision
+// will in general be sufficient.
+// Note that when the fractional JD, MJD and TJD counts are used instead
// of the integer (days,sec,ns) specification, the nanosecond precision
// may be lost due to computer accuracy w.r.t. floating point operations.
//
// the yy-mm-dd hh:mm:ss:ns TTimeStamp from a given input (M/T)JD and time.
// Obviously this TTimeStamp implementation would prevent usage of values
// smaller than JD=2440587.5 or MJD=40587 or TJD=587.
+// Furthermore, due to a limitation on the "seconds since the EPOCH start" count
+// in TTimeStamp, the latest accessible date/time is 19-jan-2038 02:14:08 UTC.
// However, this AliTimestamp facility provides support for the full range
// of (M/T)JD values, but the setting of the corresponding TTimeStamp parameters
// is restricted to the values allowed by the TTimeStamp implementation.
-// For these earlier (M/T)JD values, the standard TTimeStamp parameters will
+// For these earlier/later (M/T)JD values, the standard TTimeStamp parameters will
// be set corresponding to the start of the TTimeStamp EPOCH.
-// This implies that for these earlier (M/T)JD values the TTimeStamp parameters
+// This implies that for these earlier/later (M/T)JD values the TTimeStamp parameters
// do not match the Julian parameters of AliTimestamp.
// As such the standard TTimeStamp parameters do not appear on the print output
-// when invoking the Date() memberfunction for these earlier (M/T)JD values.
+// when invoking the Date() memberfunction for these earlier/later (M/T)JD values.
//
// Examples :
// ==========
//
// t.Date();
//
+// // Time intervals for e.g. trigger or TOF analysis
+// AliEvent evt;
+// AliTrack* tx=evt.GetTrack(5);
+// AliTimestamp* timex=tx->GetTimestamp();
+// Double_t dt=evt.GetDifference(timex,"ps");
+// AliTimestamp trig((AliTimestamp)evt);
+// trig.Add(0,0,2,173);
+// AliSignal* sx=evt.GetHit(23);
+// AliTimestamp* timex=sx->GetTimestamp();
+// Double_t dt=trig.GetDifference(timex,"ps");
+// Int_t d,s,ns,ps;
+// trig.GetDifference(timex,d,s,ns,ps);
+//
// // Some practical conversion facilities
// // Note : They don't influence the actual date/time settings
// // and as such can also be invoked as AliTimestamp::Convert(...) etc...
//- Modified: NvE $Date$ Utrecht University.
///////////////////////////////////////////////////////////////////////////
+#include <cstdlib>
#include "AliTimestamp.h"
#include "Riostream.h"
// in the docs of TTimeStamp.
FillJulian();
+ fJps=0;
}
///////////////////////////////////////////////////////////////////////////
AliTimestamp::AliTimestamp(TTimeStamp& t) : TTimeStamp(t)
// All attributes are initialised to the values of the input TTimeStamp.
FillJulian();
+ fJps=0;
}
///////////////////////////////////////////////////////////////////////////
AliTimestamp::~AliTimestamp()
fMJD=t.fMJD;
fJsec=t.fJsec;
fJns=t.fJns;
+ fJps=t.fJps;
fCalcs=t.fCalcs;
fCalcns=t.fCalcns;
}
///////////////////////////////////////////////////////////////////////////
-void AliTimestamp::Date(Int_t mode)
+void AliTimestamp::Date(Int_t mode,Double_t offset)
{
// Print date/time info.
//
-// mode = 1 ==> Only the TTimeStamp yy-mm-dd hh:mm:ss:ns info is printed
+// mode = 1 ==> Only the UT yy-mm-dd hh:mm:ss.sss and GMST info is printed
// 2 ==> Only the Julian parameter info is printed
-// 3 ==> Both the TTimeStamp and Julian parameter info is printed
+// 3 ==> Both the UT, GMST and Julian parameter info is printed
+// -1 ==> Only the UT yy-mm-dd hh:mm:ss.sss and GAST info is printed
+// -3 ==> Both the UT, GAST and Julian parameter info is printed
//
-// The default is mode=3.
+// offset : Local time offset from UT (and also GMST) in fractional hours.
+//
+// When an offset value is specified, the corresponding local times
+// LT and LMST (or LAST) are printed as well.
+//
+// The default values are mode=3 and offset=0.
//
// Note : In case the (M/T)JD falls outside the TTimeStamp range,
-// the TTimeStamp info will not be printed.
+// the yy-mm-dd info will be omitted.
+
+ Int_t mjd,mjsec,mjns,mjps;
+ GetMJD(mjd,mjsec,mjns);
+ mjps=GetPs();
- Int_t mjd,mjsec,mjns;
- GetMJD(mjd,mjsec,mjns);
+ TString month[12]={"Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"};
+ TString day[7]={"Mon","Tue","Wed","Thu","Fri","Sat","Sun"};
+ UInt_t y,m,d,wd;
+ Int_t hh,mm,ss,ns,ps;
+ Double_t gast;
+
+ if (abs(mode)==1 || abs(mode)==3)
+ {
+ if (mjd>=40587 && (mjd<65442 || (mjd==65442 && mjsec<8047)))
+ {
+ GetDate(kTRUE,0,&y,&m,&d);
+ wd=GetDayOfWeek(kTRUE,0);
+ cout << " " << day[wd-1].Data() << ", " << setfill('0') << setw(2) << d << " "
+ << setfill(' ') << month[m-1].Data() << " " << y << " ";
+ }
+ else
+ {
+ cout << " Time ";
+ }
+ GetUT(hh,mm,ss,ns,ps);
+ cout << setfill('0') << setw(2) << hh << ":"
+ << setw(2) << mm << ":" << setw(2) << ss << "."
+ << setw(9) << ns << setw(3) << ps << " (UT) ";
+ if (mode>0)
+ {
+ GetGMST(hh,mm,ss,ns,ps);
+ }
+ else
+ {
+ gast=GetGAST();
+ Convert(gast,hh,mm,ss,ns,ps);
+ }
+ cout << setfill('0') << setw(2) << hh << ":"
+ << setw(2) << mm << ":" << setw(2) << ss << "."
+ << setw(9) << ns << setw(3) << ps;
+ if (mode>0)
+ {
+ cout << " (GMST)" << endl;
+ }
+ else
+ {
+ cout << " (GAST)" << endl;
+ }
- if ((mode==1 || mode==3) && mjd>=40587) cout << " " << AsString() << endl;
- if (mode==2 || mode==3)
+ // Local time information
+ if (offset)
+ {
+ // Determine the new date by including the offset
+ AliTimestamp t2(*this);
+ t2.Add(offset);
+ Int_t mjd2,mjsec2,mjns2;
+ t2.GetMJD(mjd2,mjsec2,mjns2);
+ if (mjd2>=40587 && (mjd2<65442 || (mjd2==65442 && mjsec2<8047)))
+ {
+ t2.GetDate(kTRUE,0,&y,&m,&d);
+ wd=t2.GetDayOfWeek(kTRUE,0);
+ cout << " " << day[wd-1].Data() << ", " << setfill('0') << setw(2) << d << " "
+ << setfill(' ') << month[m-1].Data() << " " << y << " ";
+ }
+ else
+ {
+ cout << " Time ";
+ }
+ // Determine the local time by including the offset w.r.t. the original timestamp
+ Double_t hlt=GetLT(offset);
+ Double_t hlst=0;
+ if (mode>0)
+ {
+ hlst=GetLMST(offset);
+ }
+ else
+ {
+ hlst=GetLAST(offset);
+ }
+ PrintTime(hlt,12); cout << " (LT) "; PrintTime(hlst,12);
+ if (mode>0)
+ {
+ cout << " (LMST)" << endl;
+ }
+ else
+ {
+ cout << " (LAST)" << endl;
+ }
+ }
+ }
+ if (abs(mode)==2 || abs(mode)==3)
{
Int_t jd,jsec,jns;
GetJD(jd,jsec,jns);
Int_t tjd,tjsec,tjns;
GetTJD(tjd,tjsec,tjns);
- cout << " Julian Epoch : " << setprecision(25) << GetJE() << endl;
- cout << " JD : " << jd << " sec : " << jsec << " ns : " << jns
+ cout << " Julian Epoch : " << setprecision(25) << GetJE()
+ << " Besselian Epoch : " << setprecision(25) << GetBE() << endl;
+ cout << " JD : " << jd << " sec : " << jsec << " ns : " << jns << " ps : " << fJps
<< " Fractional : " << setprecision(25) << GetJD() << endl;
- cout << " MJD : " << mjd << " sec : " << mjsec << " ns : " << mjns
+ cout << " MJD : " << mjd << " sec : " << mjsec << " ns : " << mjns << " ps : " << fJps
<< " Fractional : " << setprecision(25) << GetMJD() << endl;
- cout << " TJD : " << tjd << " sec : " << tjsec << " ns : " << tjns
+ cout << " TJD : " << tjd << " sec : " << tjsec << " ns : " << tjns << " ps : " << fJps
<< " Fractional : " << setprecision(25) << GetTJD() << endl;
}
}
return je;
}
///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetBE(Double_t date,TString mode) const
+{
+// Provide the Besselian Epoch (JE) corresponding to the specified date.
+// The argument "mode" indicates the type of the argument "date".
+//
+// Available modes are :
+// mode = "jd" ==> date represents the Julian Date
+// = "mjd" ==> date represents the Modified Julian Date
+// = "tjd" ==> date represents the Truncated Julian Date
+//
+// The default is mode="jd".
+//
+// In case of invalid input, a value of -99999 is returned.
+//
+// Note :
+// ------
+// This memberfunction only provides the BE corresponding to the
+// input arguments. It does NOT set the corresponding Julian parameters
+// for the current AliTimestamp instance.
+// As such the TTimeStamp limitations do NOT apply to this memberfunction.
+// To set the Julian parameters for the current AliTimestamp instance,
+// please use the corresponding SET() memberfunctions of either AliTimestamp
+// or TTimeStamp.
+
+ if ((mode != "jd") && (mode != "mjd") && (mode != "tjd")) return -99999;
+
+ Double_t jd=date;
+ if (mode=="mjd") jd=date+2400000.5;
+ if (mode=="tjd") jd=date+2440000.5;
+
+ Double_t be=1900.+(jd-2415020.31352)/365.242198781;
+
+ return be;
+}
+///////////////////////////////////////////////////////////////////////////
void AliTimestamp::Convert(Double_t date,Int_t& days,Int_t& secs,Int_t& ns) const
{
// Convert date as fractional day count into integer days, secs and ns.
return date;
}
///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::Convert(Double_t h,Int_t& hh,Int_t& mm,Int_t& ss,Int_t& ns,Int_t& ps) const
+{
+// Convert fractional hour count h into hh:mm:ss:ns:ps.
+// The sign of the input value will be neglected, so h<0 will result in
+// the same output values as h>0.
+//
+// Note : Due to computer accuracy the ps value may become inaccurate.
+//
+// Note :
+// ------
+// This memberfunction only converts the input "h" into the corresponding
+// integer parameters. It does NOT set the corresponding Julian parameters
+// for the current AliTimestamp instance.
+// As such the TTimeStamp limitations do NOT apply to this memberfunction.
+// To set the Julian parameters for the current AliTimestamp instance,
+// please use the corresponding SET() memberfunctions of either AliTimestamp
+// or TTimeStamp.
+
+ // Neglect sign of h
+ h=fabs(h);
+
+ hh=int(h);
+ h=h-double(hh);
+ h=h*60.;
+ mm=int(h);
+ h=h-double(mm);
+ h=h*60.;
+ ss=int(h);
+ h=h-double(ss);
+ h=h*1.e9;
+ ns=int(h);
+ h=h-double(ns);
+ h=h*1000.;
+ ps=int(h);
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::Convert(Double_t h,Int_t& hh,Int_t& mm,Double_t& ss) const
+{
+// Convert fractional hour count h into hh:mm:ss.s.
+// The sign of the input value will be neglected, so h<0 will result in
+// the same output values as h>0.
+//
+// Notes :
+// -------
+// 1) This memberfunction only converts the input "h" into the corresponding
+// hh:mm:ss.s values. It does NOT set the corresponding Julian parameters
+// for the current AliTimestamp instance.
+// As such the TTimeStamp limitations do NOT apply to this memberfunction.
+// To set the Julian parameters for the current AliTimestamp instance,
+// please use the corresponding SET() memberfunctions of either AliTimestamp
+// or TTimeStamp.
+// 2) This facility can also be used to convert degrees in arcminutes etc...
+
+ // Neglect sign of h
+ h=fabs(h);
+
+ hh=int(h);
+ h=h-double(hh);
+ h=h*60.;
+ mm=int(h);
+ h=h-double(mm);
+ ss=h*60.;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::Convert(Int_t hh,Int_t mm,Int_t ss,Int_t ns,Int_t ps) const
+{
+// Convert hh:mm:ss:ns:ps into fractional hour count.
+// The sign of the input values will be neglected, so the output value
+// will always correspond to a positive hh:mm:ss:ns:ps specification.
+//
+// Note : Due to computer accuracy the ps precision may be lost.
+//
+// Note :
+// ------
+// This memberfunction only converts the input integer parameters into the
+// corresponding fractional hour count. It does NOT set the corresponding
+// Julian parameters for the current AliTimestamp instance.
+// As such the TTimeStamp limitations do NOT apply to this memberfunction.
+// To set the Julian parameters for the current AliTimestamp instance,
+// please use the corresponding SET() memberfunctions of either AliTimestamp
+// or TTimeStamp.
+
+ // Neglect the sign of the input values
+ hh=abs(hh);
+ mm=abs(mm);
+ ss=abs(ss);
+ ns=abs(ns);
+ ps=abs(ps);
+
+ Double_t h=hh;
+ h+=double(mm)/60.+(double(ss)+double(ns)*1.e-9+double(ps)*1.e-12)/3600.;
+
+ return h;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::Convert(Int_t hh,Int_t mm,Double_t ss) const
+{
+// Convert hh:mm:ss.s into fractional hour count.
+// The sign of the input values will be neglected, so the output value
+// will always correspond to a positive hh:mm:ss.s specification.
+//
+// Notes :
+// -------
+// 1) This memberfunction only converts the input hh:mm:ss.s data into the
+// corresponding fractional hour count. It does NOT set the corresponding
+// Julian parameters for the current AliTimestamp instance.
+// As such the TTimeStamp limitations do NOT apply to this memberfunction.
+// To set the Julian parameters for the current AliTimestamp instance,
+// please use the corresponding SET() memberfunctions of either AliTimestamp
+// or TTimeStamp.
+// 2) This facility can also be used to convert ddd:mm:ss.s into fractional degrees.
+
+ // Neglect the sign of the input values
+ hh=abs(hh);
+ mm=abs(mm);
+ ss=fabs(ss);
+
+ Double_t h=hh;
+ h+=double(mm)/60.+ss/3600.;
+
+ return h;
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::PrintTime(Double_t h,Int_t ndig) const
+{
+// Print a fractional hour count in hh:mm:ss.ssss format.
+// The range of the printed hour value is : -24 < hh < 24.
+// The argument "ndig" specifies the number of digits for the fractional
+// seconds (e.g. ndig=6 corresponds to microsecond precision).
+// No rounding will be performed, so a second count of 3.473 with ndig=1
+// will appear as 03.4 on the output.
+// Due to computer accuracy, precision on the picosecond level may get lost.
+//
+// The default is ndig=1.
+//
+// Note : The time info is printed without additional spaces or "endline".
+// This allows the print to be included in various composite output formats.
+
+ Int_t hh,mm,ss;
+ ULong64_t sfrac;
+ Double_t s;
+
+ while (h<-24)
+ {
+ h+=24.;
+ }
+ while (h>24)
+ {
+ h-=24.;
+ }
+
+ Convert(h,hh,mm,s);
+ ss=Int_t(s);
+ s-=Double_t(ss);
+ s*=pow(10.,ndig);
+ sfrac=ULong64_t(s);
+
+ if (h<0) cout << "-";
+ cout << setfill('0')
+ << setw(2) << hh << ":" << setw(2) << mm << ":"
+ << setw(2) << ss << "." << setw(ndig) << sfrac;
+}
+///////////////////////////////////////////////////////////////////////////
void AliTimestamp::FillJulian()
{
// Calculation and setting of the Julian date/time parameters corresponding
fCalcns=GetNanoSec();
}
///////////////////////////////////////////////////////////////////////////
-void AliTimestamp::GetMJD(Int_t& mjd,Int_t& sec, Int_t& ns)
+void AliTimestamp::GetMJD(Int_t& mjd,Int_t& sec,Int_t& ns)
{
// Provide the Modified Julian Date (MJD) and time corresponding to the
// currently stored AliTimestamp date/time parameters.
return je;
}
///////////////////////////////////////////////////////////////////////////
-void AliTimestamp::SetMJD(Int_t mjd,Int_t sec,Int_t ns)
+Double_t AliTimestamp::GetBE()
+{
+// Provide the Besselian Epoch (BE) corresponding to the currently stored
+// AliTimestamp date/time parameters.
+
+ Double_t jd=GetJD();
+ Double_t be=GetBE(jd);
+ return be;
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::SetMJD(Int_t mjd,Int_t sec,Int_t ns,Int_t ps)
{
// Set the Modified Julian Date (MJD) and time and update the TTimeStamp
// parameters accordingly (if possible).
// the yy-mm-dd hh:mm:ss:ns TTimeStamp from a given input MJD and time.
// Obviously this TTimeStamp implementation would prevent usage of MJD values
// smaller than 40587.
+// Furthermore, due to a limitation on the "seconds since the EPOCH start" count
+// in TTimeStamp, the latest accessible date/time is 19-jan-2038 02:14:08 UTC.
// However, this AliTimestamp facility provides support for the full range
// of (M)JD values, but the setting of the corresponding TTimeStamp parameters
// is restricted to the values allowed by the TTimeStamp implementation.
-// For these earlier MJD values, the standard TTimeStamp parameters will
+// For these earlier/later MJD values, the standard TTimeStamp parameters will
// be set corresponding to the start of the TTimeStamp EPOCH.
-// This implies that for these earlier MJD values the TTimeStamp parameters
+// This implies that for these earlier/later MJD values the TTimeStamp parameters
// do not match the Julian parameters of AliTimestamp.
//
// The input arguments represent the following :
// mjd : The modified Julian date.
// sec : The number of seconds elapsed within the MJD.
// ns : The remaining fractional number of seconds (in ns) elapsed within the MJD.
+// ps : The remaining fractional number of nanoseconds (in ps) elapsed within the MJD.
+//
+// Note : ps=0 is the default value.
- if (sec<0 || ns<0)
+ if (sec<0 || sec>=24*3600 || ns<0 || ns>=1e9 || ps<0 || ps>=1000)
{
cout << " *AliTimestamp::SetMJD* Invalid input."
<< " sec : " << sec << " ns : " << ns << endl;
fMJD=mjd;
fJsec=sec;
fJns=ns;
+ fJps=ps;
- Int_t epoch=40587;
+ Int_t epoch=40587; // MJD of the start of the epoch
+ Int_t limit=65442; // MJD of the latest possible TTimeStamp date/time
- if (mjd<epoch)
+ Int_t date,time;
+ if (mjd<epoch || mjd>limit || (mjd==limit && sec>=8047))
{
Set(0,kFALSE,0,kFALSE);
+ date=GetDate();
+ time=GetTime();
+ Set(date,time,0,kTRUE,0);
}
else
{
UInt_t secs=days*24*3600;
secs+=sec;
Set(secs,kFALSE,0,kFALSE);
- Int_t date=GetDate();
- Int_t time=GetTime();
+ date=GetDate();
+ time=GetTime();
Set(date,time,ns,kTRUE,0);
}
// the yy-mm-dd hh:mm:ss:ns TTimeStamp from a given input MJD and time.
// Obviously this TTimeStamp implementation would prevent usage of MJD values
// smaller than 40587.
+// Furthermore, due to a limitation on the "seconds since the EPOCH start" count
+// in TTimeStamp, the latest accessible date/time is 19-jan-2038 02:14:08 UTC.
// However, this AliTimestamp facility provides support for the full range
// of (M)JD values, but the setting of the corresponding TTimeStamp parameters
// is restricted to the values allowed by the TTimeStamp implementation.
-// For these earlier MJD values, the standard TTimeStamp parameters will
+// For these earlier/later MJD values, the standard TTimeStamp parameters will
// be set corresponding to the start of the TTimeStamp EPOCH.
-// This implies that for these earlier MJD values the TTimeStamp parameters
+// This implies that for these earlier/later MJD values the TTimeStamp parameters
// do not match the Julian parameters of AliTimestamp.
//
// Due to computer accuracy the ns precision may be lost.
SetMJD(days,secs,ns);
}
///////////////////////////////////////////////////////////////////////////
-void AliTimestamp::SetJD(Int_t jd,Int_t sec,Int_t ns)
+void AliTimestamp::SetJD(Int_t jd,Int_t sec,Int_t ns,Int_t ps)
{
// Set the Julian Date (JD) and time and update the TTimeStamp
// parameters accordingly (if possible).
// the yy-mm-dd hh:mm:ss:ns TTimeStamp from a given input MJD and time.
// Obviously this TTimeStamp implementation would prevent usage of values
// smaller than JD=2440587.5.
+// Furthermore, due to a limitation on the "seconds since the EPOCH start" count
+// in TTimeStamp, the latest accessible date/time is 19-jan-2038 02:14:08 UTC.
// However, this AliTimestamp facility provides support for the full range
// of (M)JD values, but the setting of the corresponding TTimeStamp parameters
// is restricted to the values allowed by the TTimeStamp implementation.
-// For these earlier JD values, the standard TTimeStamp parameters will
+// For these earlier/later JD values, the standard TTimeStamp parameters will
// be set corresponding to the start of the TTimeStamp EPOCH.
-// This implies that for these earlier (M)JD values the TTimeStamp parameters
+// This implies that for these earlier/later (M)JD values the TTimeStamp parameters
// do not match the Julian parameters of AliTimestamp.
//
// The input arguments represent the following :
// jd : The Julian date.
// sec : The number of seconds elapsed within the JD.
// ns : The remaining fractional number of seconds (in ns) elapsed within the JD.
+// ps : The remaining fractional number of nanoseconds (in ps) elapsed within the JD.
+//
+// Note : ps=0 is the default value.
Int_t mjd=jd-2400000;
sec-=12*3600;
mjd-=1;
}
- SetMJD(mjd,sec,ns);
+ SetMJD(mjd,sec,ns,ps);
}
///////////////////////////////////////////////////////////////////////////
void AliTimestamp::SetJD(Double_t jd)
// the yy-mm-dd hh:mm:ss:ns TTimeStamp from a given input MJD and time.
// Obviously this TTimeStamp implementation would prevent usage of values
// smaller than JD=2440587.5.
+// Furthermore, due to a limitation on the "seconds since the EPOCH start" count
+// in TTimeStamp, the latest accessible date/time is 19-jan-2038 02:14:08 UTC.
// However, this AliTimestamp facility provides support for the full range
// of (M)JD values, but the setting of the corresponding TTimeStamp parameters
// is restricted to the values allowed by the TTimeStamp implementation.
-// For these earlier JD values, the standard TTimeStamp parameters will
+// For these earlier/later JD values, the standard TTimeStamp parameters will
// be set corresponding to the start of the TTimeStamp EPOCH.
-// This implies that for these earlier (M)JD values the TTimeStamp parameters
+// This implies that for these earlier/later (M)JD values the TTimeStamp parameters
// do not match the Julian parameters of AliTimestamp.
//
// Due to computer accuracy the ns precision may be lost.
SetJD(days,secs,ns);
}
///////////////////////////////////////////////////////////////////////////
-void AliTimestamp::SetTJD(Int_t tjd,Int_t sec,Int_t ns)
+void AliTimestamp::SetTJD(Int_t tjd,Int_t sec,Int_t ns,Int_t ps)
{
// Set the Truncated Julian Date (TJD) and time and update the TTimeStamp
// parameters accordingly (if possible).
// the yy-mm-dd hh:mm:ss:ns TTimeStamp from a given input MJD and time.
// Obviously this TTimeStamp implementation would prevent usage of values
// smaller than TJD=587.
+// Furthermore, due to a limitation on the "seconds since the EPOCH start" count
+// in TTimeStamp, the latest accessible date/time is 19-jan-2038 02:14:08 UTC.
// However, this AliTimestamp facility provides support for the full range
// of (T)JD values, but the setting of the corresponding TTimeStamp parameters
// is restricted to the values allowed by the TTimeStamp implementation.
-// For these earlier JD values, the standard TTimeStamp parameters will
+// For these earlier/later JD values, the standard TTimeStamp parameters will
// be set corresponding to the start of the TTimeStamp EPOCH.
-// This implies that for these earlier (T)JD values the TTimeStamp parameters
+// This implies that for these earlier/later (T)JD values the TTimeStamp parameters
// do not match the Julian parameters of AliTimestamp.
//
// The input arguments represent the following :
// tjd : The Truncated Julian date.
// sec : The number of seconds elapsed within the JD.
// ns : The remaining fractional number of seconds (in ns) elapsed within the JD.
+// ps : The remaining fractional number of nanoseconds (in ps) elapsed within the JD.
+//
+// Note : ps=0 is the default value.
Int_t mjd=tjd+40000;
- SetMJD(mjd,sec,ns);
+ SetMJD(mjd,sec,ns,ps);
}
///////////////////////////////////////////////////////////////////////////
void AliTimestamp::SetTJD(Double_t tjd)
// the yy-mm-dd hh:mm:ss:ns TTimeStamp from a given input MJD and time.
// Obviously this TTimeStamp implementation would prevent usage of values
// smaller than TJD=587.
+// Furthermore, due to a limitation on the "seconds since the EPOCH start" count
+// in TTimeStamp, the latest accessible date/time is 19-jan-2038 02:14:08 UTC.
// However, this AliTimestamp facility provides support for the full range
// of (T)JD values, but the setting of the corresponding TTimeStamp parameters
// is restricted to the values allowed by the TTimeStamp implementation.
-// For these earlier JD values, the standard TTimeStamp parameters will
+// For these earlier/later JD values, the standard TTimeStamp parameters will
// be set corresponding to the start of the TTimeStamp EPOCH.
-// This implies that for these earlier (T)JD values the TTimeStamp parameters
+// This implies that for these earlier/later (T)JD values the TTimeStamp parameters
// do not match the Julian parameters of AliTimestamp.
//
// Due to computer accuracy the ns precision may be lost.
SetTJD(days,secs,ns);
}
///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::SetNs(Int_t ns)
+{
+// Set the remaining fractional number of seconds in nanosecond precision.
+// Notes :
+// -------
+// 1) The allowed range for the argument "ns" is [0,99999999].
+// Outside that range no action is performed.
+// 2) The ns fraction can also be entered directly via SetMJD() etc...
+// 3) For additional accuracy see SetPs().
+
+ if (ns>=0 && ns<=99999999) fJns=ns;
+}
+///////////////////////////////////////////////////////////////////////////
+Int_t AliTimestamp::GetNs() const
+{
+// Provide the remaining fractional number of seconds in nanosecond precision.
+// This function allows trigger/timing analysis for (astro)particle physics
+// experiments.
+// Note : For additional accuracy see also GetPs().
+
+ return fJns;
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::SetPs(Int_t ps)
+{
+// Set the remaining fractional number of nanoseconds in picoseconds.
+// Notes :
+// -------
+// 1) The allowed range for the argument "ps" is [0,999].
+// Outside that range no action is performed.
+// 2) The ps fraction can also be entered directly via SetMJD() etc...
+
+ if (ps>=0 && ps<=999) fJps=ps;
+}
+///////////////////////////////////////////////////////////////////////////
+Int_t AliTimestamp::GetPs() const
+{
+// Provide remaining fractional number of nanoseconds in picoseconds.
+// This function allows time of flight analysis for particle physics
+// experiments.
+
+ return fJps;
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::Add(Int_t d,Int_t s,Int_t ns,Int_t ps)
+{
+// Add (or subtract) a certain time difference to the current timestamp.
+// Subtraction can be achieved by entering negative values as input arguments.
+//
+// The time difference is entered via the following input arguments :
+//
+// d : elapsed number of days
+// s : (remaining) elapsed number of seconds
+// ns : (remaining) elapsed number of nanoseconds
+// ps : (remaining) elapsed number of picoseconds
+//
+// The specified d, s, ns and ps values will be used in an additive
+// way to determine the time difference.
+// So, specification of d=1, s=100, ns=0, ps=0 will result in the
+// same time difference addition as d=0, s=24*3600+100, ns=0, ps=0.
+// However, by making use of the latter the user should take care
+// of possible integer overflow problems in the input arguments,
+// which obviously will provide incorrect results.
+//
+// Note : ps=0 is the default value.
+
+ Int_t days=0;
+ Int_t secs=0;
+ Int_t nsec=0;
+ // Use Get functions to ensure updated Julian parameters.
+ GetMJD(days,secs,nsec);
+ Int_t psec=GetPs();
+
+ psec+=ps%1000;
+ nsec+=ps/1000;
+ while (psec<0)
+ {
+ nsec-=1;
+ psec+=1000;
+ }
+ while (psec>999)
+ {
+ nsec+=1;
+ psec-=1000;
+ }
+
+ nsec+=ns%1000000000;
+ secs+=ns/1000000000;
+ while (nsec<0)
+ {
+ secs-=1;
+ nsec+=1000000000;
+ }
+ while (nsec>999999999)
+ {
+ secs+=1;
+ nsec-=1000000000;
+ }
+
+ secs+=s%(24*3600);
+ days+=s/(24*3600);
+ while (secs<0)
+ {
+ days-=1;
+ secs+=24*3600;
+ }
+ while (secs>=24*3600)
+ {
+ days+=1;
+ secs-=24*3600;
+ }
+
+ days+=d;
+
+ SetMJD(days,secs,nsec,psec);
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::Add(Double_t hours)
+{
+// Add (or subtract) a certain time difference to the current timestamp.
+// The time difference is specified as a (fractional) number of hours.
+// Subtraction can be achieved by entering a negative value as input argument.
+
+ Int_t d,s,ns,ps;
+ Double_t h=fabs(hours);
+ d=int(h/24.);
+ h-=double(d)*24.;
+ h*=3600.;
+ s=int(h);
+ h-=double(s);
+ h*=1.e9;
+ ns=int(h);
+ h-=double(ns);
+ ps=int(h*1000.);
+ if (hours>0) Add(d,s,ns,ps);
+ if (hours<0) Add(-d,-s,-ns,-ps);
+}
+///////////////////////////////////////////////////////////////////////////
+Int_t AliTimestamp::GetDifference(AliTimestamp* t,Int_t& d,Int_t& s,Int_t& ns,Int_t& ps)
+{
+// Provide the time difference w.r.t the AliTimestamp specified on the input.
+// This memberfunction supports both very small (i.e. time of flight analysis
+// for particle physics experiments) and very long (i.e. investigation of
+// astrophysical phenomena) timescales.
+//
+// The time difference is returned via the following output arguments :
+// d : elapsed number of days
+// s : remaining elapsed number of seconds
+// ns : remaining elapsed number of nanoseconds
+// ps : remaining elapsed number of picoseconds
+//
+// Note :
+// ------
+// The calculated time difference is the absolute value of the time interval.
+// This implies that the values of d, s, ns and ps are always positive or zero.
+//
+// The integer return argument indicates whether the AliTimestamp specified
+// on the input argument occurred earlier (-1), simultaneously (0) or later (1).
+
+ if (!t) return 0;
+
+ // Ensure updated Julian parameters for this AliTimestamp instance
+ if (fCalcs != GetSec() || fCalcns != GetNanoSec()) FillJulian();
+
+ // Use Get functions to ensure updated Julian parameters.
+ t->GetMJD(d,s,ns);
+ ps=t->GetPs();
+
+ d-=fMJD;
+ s-=fJsec;
+ ns-=fJns;
+ ps-=fJps;
+
+ if (!d && !s && !ns && !ps) return 0;
+
+ Int_t sign=0;
+
+ if (d>0) sign=1;
+ if (d<0) sign=-1;
+
+ if (!sign && s>0) sign=1;
+ if (!sign && s<0) sign=-1;
+
+ if (!sign && ns>0) sign=1;
+ if (!sign && ns<0) sign=-1;
+
+ if (!sign && ps>0) sign=1;
+ if (!sign && ps<0) sign=-1;
+
+ // In case the input stamp was earlier, take the reverse difference
+ // to simplify the algebra.
+ if (sign<0)
+ {
+ d=-d;
+ s=-s;
+ ns=-ns;
+ ps=-ps;
+ }
+
+ // Here we always have a positive time difference
+ // and can now unambiguously correct for other negative values.
+ if (ps<0)
+ {
+ ns-=1;
+ ps+=1000;
+ }
+
+ if (ns<0)
+ {
+ s-=1;
+ ns+=1000000000;
+ }
+
+ if (s<0)
+ {
+ d-=1;
+ s+=24*3600;
+ }
+
+ return sign;
+}
+///////////////////////////////////////////////////////////////////////////
+Int_t AliTimestamp::GetDifference(AliTimestamp& t,Int_t& d,Int_t& s,Int_t& ns,Int_t& ps)
+{
+// Provide the time difference w.r.t the AliTimestamp specified on the input.
+// This memberfunction supports both very small (i.e. time of flight analysis
+// for particle physics experiments) and very long (i.e. investigation of
+// astrophysical phenomena) timescales.
+//
+// The time difference is returned via the following output arguments :
+// d : elapsed number of days
+// s : remaining elapsed number of seconds
+// ns : remaining elapsed number of nanoseconds
+// ps : remaining elapsed number of picoseconds
+//
+// Note :
+// ------
+// The calculated time difference is the absolute value of the time interval.
+// This implies that the values of d, s, ns and ps are always positive or zero.
+//
+// The integer return argument indicates whether the AliTimestamp specified
+// on the input argument occurred earlier (-1), simultaneously (0) or later (1).
+
+ return GetDifference(&t,d,s,ns,ps);
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetDifference(AliTimestamp* t,TString u,Int_t mode)
+{
+// Provide the time difference w.r.t the AliTimestamp specified on the input
+// argument in the units as specified by the TString argument.
+// A positive return value means that the AliTimestamp specified on the input
+// argument occurred later, whereas a negative return value indicates an
+// earlier occurence.
+//
+// The units may be specified as :
+// u = "d" ==> Time difference returned as (fractional) day count
+// "s" ==> Time difference returned as (fractional) second count
+// "ns" ==> Time difference returned as (fractional) nanosecond count
+// "ps" ==> Time difference returned as picosecond count
+//
+// It may be clear that for a time difference of several days, the picosecond
+// and even the nanosecond accuracy may be lost.
+// To cope with this, the "mode" argument has been introduced to allow
+// timestamp comparison on only the specified units.
+//
+// The following operation modes are supported :
+// mode = 1 : Full time difference is returned in specified units
+// 2 : Time difference is returned in specified units by
+// neglecting the elapsed time for the larger units than the
+// ones specified.
+// 3 : Time difference is returned in specified units by only
+// comparing the timestamps on the level of the specified units.
+//
+// Example :
+// ---------
+// AliTimestamp t1; // Corresponding to days=3, secs=501, ns=31, ps=7
+// AliTimestamp t2; // Corresponding to days=5, secs=535, ns=12, ps=15
+//
+// The statement : Double_t val=t1.GetDifference(t2,....)
+// would return the following values :
+// val=(2*24*3600)+34-(19*1e-9)+(8*1e-12) for u="s" and mode=1
+// val=34-(19*1e-9)+(8*1e-12) for u="s" and mode=2
+// val=34 for u="s" and mode=3
+// val=-19 for u="ns" and mode=3
+//
+// The default is mode=1.
+
+ if (!t || mode<1 || mode>3) return 0;
+
+ Double_t dt=0;
+
+ // Ensure updated Julian parameters for this AliTimestamp instance
+ if (fCalcs != GetSec() || fCalcns != GetNanoSec()) FillJulian();
+
+ Int_t dd=0;
+ Int_t ds=0;
+ Int_t dns=0;
+ Int_t dps=0;
+
+ // Use Get functions to ensure updated Julian parameters.
+ t->GetMJD(dd,ds,dns);
+ dps=t->GetPs();
+
+ dd-=fMJD;
+ ds-=fJsec;
+ dns-=fJns;
+ dps-=fJps;
+
+ // Time difference for the specified units only
+ if (mode==3)
+ {
+ if (u=="d") dt=dd;
+ if (u=="s") dt=ds;
+ if (u=="ns") dt=dns;
+ if (u=="ps") dt=dps;
+ return dt;
+ }
+
+ // Suppress elapsed time for the larger units than specified
+ if (mode==2)
+ {
+ if (u=="s") dd=0;
+ if (u=="ns")
+ {
+ dd=0;
+ ds=0;
+ }
+ if (u=="ps")
+ {
+ dd=0;
+ ds=0;
+ dns=0;
+ }
+ }
+
+ // Compute the time difference as requested
+ if (u=="s" || u=="d")
+ {
+ // The time difference in (fractional) seconds
+ dt=double(dd*24*3600+ds)+(double(dns)*1e-9)+(double(dps)*1e-12);
+ if (u=="d") dt=dt/double(24*3600);
+ }
+ if (u=="ns") dt=(double(dd*24*3600+ds)*1e9)+double(dns)+(double(dps)*1e-3);
+ if (u=="ps") dt=(double(dd*24*3600+ds)*1e12)+(double(dns)*1e3)+double(dps);
+
+ return dt;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetDifference(AliTimestamp& t,TString u,Int_t mode)
+{
+// Provide the time difference w.r.t the AliTimestamp specified on the input
+// argument in the units as specified by the TString argument.
+// A positive return value means that the AliTimestamp specified on the input
+// argument occurred later, whereas a negative return value indicates an
+// earlier occurence.
+//
+// The units may be specified as :
+// u = "d" ==> Time difference returned as (fractional) day count
+// "s" ==> Time difference returned as (fractional) second count
+// "ns" ==> Time difference returned as (fractional) nanosecond count
+// "ps" ==> Time difference returned as picosecond count
+//
+// It may be clear that for a time difference of several days, the picosecond
+// and even the nanosecond accuracy may be lost.
+// To cope with this, the "mode" argument has been introduced to allow
+// timestamp comparison on only the specified units.
+//
+// The following operation modes are supported :
+// mode = 1 : Full time difference is returned in specified units
+// 2 : Time difference is returned in specified units by
+// neglecting the elapsed time for the larger units than the
+// ones specified.
+// 3 : Time difference is returned in specified units by only
+// comparing the timestamps on the level of the specified units.
+//
+// Example :
+// ---------
+// AliTimestamp t1; // Corresponding to days=3, secs=501, ns=31, ps=7
+// AliTimestamp t2; // Corresponding to days=5, secs=535, ns=12, ps=15
+//
+// The statement : Double_t val=t1.GetDifference(t2,....)
+// would return the following values :
+// val=(2*24*3600)+34-(19*1e-9)+(8*1e-12) for u="s" and mode=1
+// val=34-(19*1e-9)+(8*1e-12) for u="s" and mode=2
+// val=34 for u="s" and mode=3
+// val=-19 for u="ns" and mode=3
+//
+// The default is mode=1.
+
+ return GetDifference(&t,u,mode);
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::SetUT(Int_t y,Int_t m,Int_t d,Int_t hh,Int_t mm,Int_t ss,Int_t ns,Int_t ps)
+{
+// Set the AliTimestamp parameters corresponding to the UT date and time
+// in the Gregorian calendar as specified by the input arguments.
+// This facility is exact upto picosecond precision and as such is
+// for scientific observations preferable above the corresponding
+// Set function(s) of TTimestamp.
+// The latter has a random spread in the sub-second part, which
+// might be of use in generating distinguishable timestamps while
+// still keeping second precision.
+//
+// The input arguments represent the following :
+// y : year in UT (e.g. 1952, 2003 etc...)
+// m : month in UT (1=jan 2=feb etc...)
+// d : day in UT (1-31)
+// hh : elapsed hours in UT (0-23)
+// mm : elapsed minutes in UT (0-59)
+// ss : elapsed seconds in UT (0-59)
+// ns : remaining fractional elapsed second of UT in nanosecond
+// ps : remaining fractional elapsed nanosecond of UT in picosecond
+//
+// Note : ns=0 and ps=0 are the default values.
+//
+// This facility first determines the elapsed days, seconds etc...
+// since the beginning of the specified UT year on basis of the
+// input arguments. Subsequently it invokes the SetUT memberfunction
+// for the elapsed timespan.
+// As such this facility is valid for all AD dates in the Gregorian
+// calendar with picosecond precision.
+
+ Int_t day=GetDayOfYear(d,m,y);
+ Int_t secs=hh*3600+mm*60+ss;
+ SetUT(y,day-1,secs,ns,ps);
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::SetUT(Int_t y,Int_t d,Int_t s,Int_t ns,Int_t ps)
+{
+// Set the AliTimestamp parameters corresponding to the specified elapsed
+// timespan since the beginning of the new UT year.
+// This facility is exact upto picosecond precision and as such is
+// for scientific observations preferable above the corresponding
+// Set function(s) of TTimestamp.
+// The latter has a random spread in the sub-second part, which
+// might be of use in generating distinguishable timestamps while
+// still keeping second precision.
+//
+// The UT year and elapsed time span is entered via the following input arguments :
+//
+// y : year in UT (e.g. 1952, 2003 etc...)
+// d : elapsed number of days
+// s : (remaining) elapsed number of seconds
+// ns : (remaining) elapsed number of nanoseconds
+// ps : (remaining) elapsed number of picoseconds
+//
+// The specified d, s, ns and ps values will be used in an additive
+// way to determine the elapsed timespan.
+// So, specification of d=1, s=100, ns=0, ps=0 will result in the
+// same elapsed time span as d=0, s=24*3600+100, ns=0, ps=0.
+// However, by making use of the latter the user should take care
+// of possible integer overflow problems in the input arguments,
+// which obviously will provide incorrect results.
+//
+// Note : ns=0 and ps=0 are the default values.
+//
+// This facility first sets the (M)JD corresponding to the start (01-jan 00:00:00)
+// of the specified UT year following the recipe of R.W. Sinnott
+// Sky & Telescope 82, (aug. 1991) 183.
+// Subsequently the day and (sub)second parts are added to the AliTimestamp.
+// As such this facility is valid for all AD dates in the Gregorian calendar.
+
+ Double_t jd=GetJD(y,1,1,0,0,0,0);
+ SetJD(jd);
+
+ Int_t mjd,sec,nsec;
+ GetMJD(mjd,sec,nsec);
+ SetMJD(mjd,0,0,0);
+ Add(d,s,ns,ps);
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::GetUT(Int_t& hh,Int_t& mm,Int_t& ss,Int_t& ns,Int_t& ps)
+{
+// Provide the corrresponding UT as hh:mm:ss:ns:ps.
+// This facility is based on the MJD, so the TTimeStamp limitations
+// do not apply here.
+
+ Int_t mjd,sec,nsec,psec;
+
+ GetMJD(mjd,sec,nsec);
+ psec=GetPs();
+
+ hh=sec/3600;
+ sec=sec%3600;
+ mm=sec/60;
+ ss=sec%60;
+ ns=nsec;
+ ps=psec;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetUT()
+{
+// Provide the corrresponding UT in fractional hours.
+// This facility is based on the MJD, so the TTimeStamp limitations
+// do not apply here.
+
+ Int_t hh,mm,ss,ns,ps;
+
+ GetUT(hh,mm,ss,ns,ps);
+
+ Double_t ut=Convert(hh,mm,ss,ns,ps);
+
+ return ut;
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::GetGMST(Int_t& hh,Int_t& mm,Int_t& ss,Int_t& ns,Int_t& ps)
+{
+// Provide the corrresponding Greenwich Mean Sideral Time (GMST).
+// The algorithm used is the one described at p. 83 of the book
+// Astronomy Methods by Hale Bradt.
+// This facility is based on the MJD, so the TTimeStamp limitations
+// do not apply here.
+
+ Int_t mjd,sec,nsec,psec;
+
+ // The current UT based timestamp data
+ GetMJD(mjd,sec,nsec);
+ psec=fJps;
+
+ // The basis for the daily corrections in units of Julian centuries w.r.t. J2000.
+ // Note : Epoch J2000 starts at 01-jan-2000 12:00:00 UT.
+ Double_t tau=(GetJD()-2451545.)/36525.;
+
+ // Syncronise sidereal time with current timestamp
+ AliTimestamp sid;
+ sid.SetMJD(mjd,sec,nsec,psec);
+
+ // Add offset for GMST start value defined as 06:41:50.54841 at 01-jan 00:00:00 UT
+ sec=6*3600+41*60+50;
+ nsec=548410000;
+ psec=0;
+ sid.Add(0,sec,nsec,psec);
+
+ // Daily correction for precession and polar motion
+ Double_t addsec=8640184.812866*tau+0.093104*pow(tau,2)-6.2e-6*pow(tau,3);
+ sec=int(addsec);
+ addsec-=double(sec);
+ nsec=int(addsec*1.e9);
+ addsec-=double(nsec)*1.e-9;
+ psec=int(addsec*1.e12);
+ sid.Add(0,sec,nsec,psec);
+
+ sid.GetMJD(mjd,sec,nsec);
+ psec=sid.GetPs();
+
+ hh=sec/3600;
+ sec=sec%3600;
+ mm=sec/60;
+ ss=sec%60;
+ ns=nsec;
+ ps=psec;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetGMST()
+{
+// Provide the corrresponding Greenwich Mean Sideral Time (GMST)
+// in fractional hours.
+// This facility is based on the MJD, so the TTimeStamp limitations
+// do not apply here.
+
+ Int_t hh,mm,ss,ns,ps;
+
+ GetGMST(hh,mm,ss,ns,ps);
+
+ Double_t gst=Convert(hh,mm,ss,ns,ps);
+
+ return gst;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetGAST()
+{
+// Provide the corrresponding Greenwich Apparent Sideral Time (GAST)
+// in fractional hours.
+// In case a hh:mm:ss.sss format is needed, please invoke the Convert()
+// memberfunction for conversion of the provided fractional hour value.
+//
+// The GAST is the GMST corrected for the shift of the vernal equinox
+// due to nutation. The right ascension component of the nutation correction
+// of the vernal equinox is called the "equation of the equinoxes".
+// So we have :
+//
+// GAST = GMST + (equation of the equinoxes)
+//
+// The equation of the equinoxes is determined via the Almanac() memberfunction.
+//
+// Since GMST is based on the MJD, the TTimeStamp limitations do not apply here.
+
+ Double_t da=Almanac();
+
+ // Convert to fractional hours
+ da/=3600.;
+
+ Double_t gast=GetGMST()+da;
+
+ while (gast<0)
+ {
+ gast+=24.;
+ }
+ while (gast>24.)
+ {
+ gast-=24.;
+ }
+
+ return gast;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetLT(Double_t offset)
+{
+// Provide the corresponding local time in fractional hours.
+// The "offset" denotes the time difference in (fractional) hours w.r.t. UT.
+// A mean solar day lasts 24h (i.e. 86400s).
+//
+// In case a hh:mm:ss format is needed, please use the Convert() facility.
+
+ // Current UT time in fractional hours
+ Double_t h=GetUT();
+
+ h+=offset;
+
+ while (h<0)
+ {
+ h+=24.;
+ }
+ while (h>24)
+ {
+ h-=24.;
+ }
+
+ return h;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetLMST(Double_t offset)
+{
+// Provide the corresponding Local Mean Sidereal Time (LMST) in fractional hours.
+// The "offset" denotes the time difference in (fractional) hours w.r.t. GMST.
+// A sidereal day corresponds to 23h 56m 04.09s (i.e. 86164.09s) mean solar time.
+// The definition of GMST is such that a sidereal clock corresponds with
+// 24 sidereal hours per revolution of the Earth.
+// As such, local time offsets w.r.t. UT and GMST can be treated similarly.
+//
+// In case a hh:mm:ss format is needed, please use the Convert() facility.
+
+ // Current GMST time in fractional hours
+ Double_t h=GetGMST();
+
+ h+=offset;
+
+ while (h<0)
+ {
+ h+=24.;
+ }
+ while (h>24)
+ {
+ h-=24.;
+ }
+
+ return h;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetLAST(Double_t offset)
+{
+// Provide the corresponding Local Apparent Sidereal Time (LAST) in fractional hours.
+// The "offset" denotes the time difference in (fractional) hours w.r.t. GAST.
+// A sidereal day corresponds to 23h 56m 04.09s (i.e. 86164.09s) mean solar time.
+// The definition of GMST and GAST is such that a sidereal clock corresponds with
+// 24 sidereal hours per revolution of the Earth.
+// As such, local time offsets w.r.t. UT, GMST and GAST can be treated similarly.
+//
+// In case a hh:mm:ss.sss format is needed, please use the Convert() facility.
+
+ // Current GAST time in fractional hours
+ Double_t h=GetGAST();
+
+ h+=offset;
+
+ while (h<0)
+ {
+ h+=24.;
+ }
+ while (h>24)
+ {
+ h-=24.;
+ }
+
+ return h;
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::SetLT(Double_t dt,Int_t y,Int_t m,Int_t d,Int_t hh,Int_t mm,Int_t ss,Int_t ns,Int_t ps)
+{
+// Set the AliTimestamp parameters corresponding to the LT date and time
+// in the Gregorian calendar as specified by the input arguments.
+// This facility is exact upto picosecond precision and as such is
+// for scientific observations preferable above the corresponding
+// Set function(s) of TTimestamp.
+// The latter has a random spread in the sub-second part, which
+// might be of use in generating distinguishable timestamps while
+// still keeping second precision.
+//
+// The input arguments represent the following :
+//
+// dt : the local time offset in fractional hours w.r.t. UT.
+// y : year in LT (e.g. 1952, 2003 etc...)
+// m : month in LT (1=jan 2=feb etc...)
+// d : day in LT (1-31)
+// hh : elapsed hours in LT (0-23)
+// mm : elapsed minutes in LT (0-59)
+// ss : elapsed seconds in LT (0-59)
+// ns : remaining fractional elapsed second of LT in nanosecond
+// ps : remaining fractional elapsed nanosecond of LT in picosecond
+//
+// Note : ns=0 and ps=0 are the default values.
+//
+// This facility first sets the UT as specified by the input arguments
+// and then corrects the UT by subtracting the local time offset w.r.t. UT.
+// As such this facility is valid for all AD dates in the Gregorian
+// calendar with picosecond precision.
+
+ SetUT(y,m,d,hh,mm,ss,ns,ps);
+ Add(-dt);
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::SetLT(Double_t dt,Int_t y,Int_t d,Int_t s,Int_t ns,Int_t ps)
+{
+// Set the AliTimestamp parameters corresponding to the specified elapsed
+// timespan since the beginning of the new LT year.
+// This facility is exact upto picosecond precision and as such is
+// for scientific observations preferable above the corresponding
+// Set function(s) of TTimestamp.
+// The latter has a random spread in the sub-second part, which
+// might be of use in generating distinguishable timestamps while
+// still keeping second precision.
+//
+// The LT year and elapsed time span is entered via the following input arguments :
+//
+// dt : the local time offset in fractional hours w.r.t. UT.
+// y : year in LT (e.g. 1952, 2003 etc...)
+// d : elapsed number of days
+// s : (remaining) elapsed number of seconds
+// ns : (remaining) elapsed number of nanoseconds
+// ps : (remaining) elapsed number of picoseconds
+//
+// The specified d, s, ns and ps values will be used in an additive
+// way to determine the elapsed timespan.
+// So, specification of d=1, s=100, ns=0, ps=0 will result in the
+// same elapsed time span as d=0, s=24*3600+100, ns=0, ps=0.
+// However, by making use of the latter the user should take care
+// of possible integer overflow problems in the input arguments,
+// which obviously will provide incorrect results.
+//
+// Note : ns=0 and ps=0 are the default values.
+//
+// This facility first sets the UT as specified by the input arguments
+// and then corrects the UT by subtracting the local time offset w.r.t. UT.
+// As such this facility is valid for all AD dates in the Gregorian calendar.
+
+ SetUT(y,d,s,ns,ps);
+ Add(-dt);
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetJD(Double_t e,TString mode) const
+{
+// Provide the fractional Julian Date from epoch e.
+// The sort of epoch may be specified via the "mode" parameter.
+//
+// mode = "J" ==> Julian epoch
+// "B" ==> Besselian epoch
+//
+// The default value is mode="J".
+
+ Double_t jd=0;
+
+ if (mode=="J" || mode=="j") jd=(e-2000.0)*365.25+2451545.0;
+
+ if (mode=="B" || mode=="b") jd=(e-1900.0)*365.242198781+2415020.31352;
+
+ return jd;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetMJD(Double_t e,TString mode) const
+{
+// Provide the fractional Modified Julian Date from epoch e.
+// The sort of epoch may be specified via the "mode" parameter.
+//
+// mode = "J" ==> Julian epoch
+// "B" ==> Besselian epoch
+//
+// The default value is mode="J".
+
+ Double_t mjd=GetJD(e,mode)-2400000.5;
+
+ return mjd;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetTJD(Double_t e,TString mode) const
+{
+// Provide the fractional Truncated Julian Date from epoch e.
+// The sort of epoch may be specified via the "mode" parameter.
+//
+// mode = "J" ==> Julian epoch
+// "B" ==> Besselian epoch
+//
+// The default value is mode="J".
+
+ Double_t tjd=GetJD(e,mode)-2440000.5;
+
+ return tjd;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::Almanac(Double_t* dpsi,Double_t* deps,Double_t* eps)
+{
+// Determination of some astronomical observables which may be needed
+// for further calculations like e.g. precession of coordinates.
+//
+// The standard returned value is the "equation of the equinoxes"
+// (i.e. the nutational shift of the RA of the vernal equinox) in seconds.
+// The memberfunction arguments provide the possibility of retrieving
+// optional returned values. The corresponding observables are :
+//
+// dpsi : Nutational shift in ecliptic longitude in arcseconds
+// deps : Nutational shift in ecliptic obliquity in arcseconds
+// eps : Mean obliquity of the ecliptic in arcseconds
+//
+// All shifts are determined for the current timestamp with
+// J2000.0 (i.e. 01-jan-2000 12:00:00 UT) as the reference epoch.
+//
+// Invokation example :
+// --------------------
+// AliTimestamp t;
+// Double_t da,dpsi,deps,eps;
+// da=t.Almanac(&dpsi,&deps,&eps);
+//
+// The nutation model used is the new one as documented in :
+// "The IAU Resolutions on Astronomical Reference Systems,
+// Time Scales and Earth Rotation Models".
+// This document is freely available as Circular 179 (2005) of the
+// United States Naval Observatory (USNO).
+// (See : http://aa.usno.navy.mil/publications/docs).
+//
+// The change in ecliptic longitude (dpsi) and ecliptic obliquity (deps)
+// are evaluated using the IAU 2000A nutation series expansion
+// as provided in the USNO Circular 179.
+// The new expression for the equation of the equinoxes is based on a series
+// expansion and is the most accurate one known to date.
+// The components are documented on p.17 of the USNO Circular 179.
+//
+// In the current implementation only the first 28 terms of the nutation series
+// are used. This provides an accuracy of about 0.01 arcsec corresponding to 0.001 sec.
+// In case a better accuracy is required, the series can be extended.
+// The total series expansion consists of 1365 terms.
+//
+// Since all calculations are based on the JD, the TTimeStamp limitations
+// do not apply here.
+
+ Double_t pi=acos(-1.);
+
+ Double_t t; // Time difference in fractional Julian centuries w.r.t. the start of J2000.
+ Double_t epsilon; // Mean obliquity of the ecliptic
+ Double_t l; // Mean anomaly of the Moon
+ Double_t lp; // Mean anomaly of the Sun
+ Double_t f; // Mean argument of latitude of the moon
+ Double_t d; // Mean elongation of the Moon from the Sun
+ Double_t om; // Mean longitude of the Moon's mean ascending mode
+
+ t=(GetJD()-2451545.0)/36525.;
+
+ // Values of epsilon and the fundamental luni-solar arguments in arcseconds
+ epsilon=84381.406-46.836769*t-0.0001831*pow(t,2)+0.00200340*pow(t,3)
+ -0.000000576*pow(t,4)-0.0000000434*pow(t,5);
+ l=485868.249036+1717915923.2178*t+31.8792*pow(t,2)+0.051635*pow(t,3)-0.00024470*pow(t,4);
+ lp=1287104.79305+129596581.0481*t-0.5532*pow(t,2)+0.000136*pow(t,3)-0.00001149*pow(t,4);
+ f=335779.526232+1739527262.8478*t-12.7512*pow(t,2)-0.001037*pow(t,3)+0.00000417*pow(t,4);
+ d=1072260.70369+1602961601.2090*t-6.3706*pow(t,2)+0.006593*pow(t,3)-0.00003169*pow(t,4);
+ om=450160.398036-6962890.5431*t+7.4722*pow(t,2)+0.007702*pow(t,3)-0.00005939*pow(t,4);
+
+ if (eps) *eps=epsilon;
+
+ // Convert to radians
+ epsilon=epsilon*pi/(180.*3600.);
+ f=f*pi/(180.*3600.);
+ d=d*pi/(180.*3600.);
+ l=l*pi/(180.*3600.);
+ lp=lp*pi/(180.*3600.);
+ om=om*pi/(180.*3600.);
+
+ //The IAU 2000A nutation series expansion.
+ Double_t phi[28]={om,2.*(f-d+om),2.*(f+om),2.*om,lp,lp+2.*(f-d+om),l,
+ 2.*f+om,l+2.*(f+om),2.*(f-d+om)-lp,2.*(f-d)+om,2.*(f+om)-l,2.*d-l,l+om,
+ om-l,2.*(f+d+om)-l,l+2.*f+om,2.*(f-l)+om,2.*d,2.*(f+d+om),2.*(f-d+om-lp),
+ 2.*(d-l),2.*(l+d+om),l+2.*(f-d+om),2.*f+om-l,2.*l,2.*f,lp+om};
+ Double_t s[28]={-17.2064161,-1.3170907,-0.2276413, 0.2074554, 0.1475877,-0.0516821, 0.0711159,
+ -0.0387298,-0.0301461, 0.0215829, 0.0128227, 0.0123457, 0.0156994, 0.0063110,
+ -0.0057976,-0.0059641,-0.0051613, 0.0045893, 0.0063384,-0.0038571, 0.0032481,
+ -0.0047722,-0.0031046, 0.0028593, 0.0020441, 0.0029243, 0.0025887,-0.0014053};
+ Double_t sd[28]={-0.0174666,-0.0001675,-0.0000234, 0.0000207,-0.0003633, 0.0001226, 0.0000073,
+ -0.0000367,-0.0000036,-0.0000494, 0.0000137, 0.0000011, 0.0000010, 0.0000063,
+ -0.0000063,-0.0000011,-0.0000042, 0.0000050, 0.0000011,-0.0000001, 0.0000000,
+ 0.0000000,-0.0000001, 0.0000000, 0.0000021, 0.0000000, 0.0000000,-0.0000025};
+ Double_t cp[28]={ 0.0033386,-0.0013696, 0.0002796,-0.0000698, 0.0011817,-0.0000524,-0.0000872,
+ 0.0000380, 0.0000816, 0.0000111, 0.0000181, 0.0000019,-0.0000168, 0.0000027,
+ -0.0000189, 0.0000149, 0.0000129, 0.0000031,-0.0000150, 0.0000158, 0.0000000,
+ -0.0000018, 0.0000131,-0.0000001, 0.0000010,-0.0000074,-0.0000066, 0.0000079};
+ Double_t c[28]= { 9.2052331, 0.5730336, 0.0978459,-0.0897492, 0.0073871, 0.0224386,-0.0006750,
+ 0.0200728, 0.0129025,-0.0095929,-0.0068982,-0.0053311,-0.0001235,-0.0033228,
+ 0.0031429, 0.0025543, 0.0026366,-0.0024236,-0.0001220, 0.0016452,-0.0013870,
+ 0.0000477, 0.0013238,-0.0012338,-0.0010758,-0.0000609,-0.0000550, 0.0008551};
+ Double_t cd[28]={ 0.0009086,-0.0003015,-0.0000485, 0.0000470,-0.0000184,-0.0000677, 0.0000000,
+ 0.0000018,-0.0000063, 0.0000299,-0.0000009, 0.0000032, 0.0000000, 0.0000000,
+ 0.0000000,-0.0000011, 0.0000000,-0.0000010, 0.0000000,-0.0000011, 0.0000000,
+ 0.0000000,-0.0000011, 0.0000010, 0.0000000, 0.0000000, 0.0000000,-0.0000002};
+ Double_t sp[28]={ 0.0015377,-0.0004587, 0.0001374,-0.0000291,-0.0001924,-0.0000174, 0.0000358,
+ 0.0000318, 0.0000367, 0.0000132, 0.0000039,-0.0000004, 0.0000082,-0.0000009,
+ -0.0000075, 0.0000066, 0.0000078, 0.0000020, 0.0000029, 0.0000068, 0.0000000,
+ -0.0000025, 0.0000059,-0.0000003,-0.0000003, 0.0000013, 0.0000011,-0.0000045};
+
+ Double_t dp=0,de=0,da=0;
+ for (Int_t i=0; i<28; i++)
+ {
+ dp+=(s[i]+sd[i]*t)*sin(phi[i])+cp[i]*cos(phi[i]);
+ de+=(c[i]+cd[i]*t)*cos(phi[i])+sp[i]*sin(phi[i]);
+ }
+
+ da=dp*cos(epsilon)+0.00264096*sin(om)+0.00006352*sin(2.*om)
+ +0.00001175*sin(2.*f-2.*d+3.*om)+0.00001121*sin(2.*f-2.*d+om)
+ -0.00000455*sin(2.*f-2.*d+2.*om)+0.00000202*sin(2.*f+3.*om)+0.00000198*sin(2.*f+om)
+ -0.00000172*sin(3.*om)-0.00000087*t*sin(om);
+
+ if (dpsi) *dpsi=dp;
+ if (deps) *deps=de;
+
+ // Convert to seconds
+ da/=15.;
+
+ return da;
+}
+///////////////////////////////////////////////////////////////////////////
+void AliTimestamp::SetEpoch(Double_t e,TString mode)
+{
+// Set the timestamp parameters according to the epoch as specified by
+// the input argument "e".
+// Via the input argument "mode" the user can specify the type of epoch
+//
+// mode = "B" ==> Besselian epoch
+// "J" ==> Julian epoch
+
+ Double_t jd=GetJD(e,mode);
+ SetJD(jd);
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t AliTimestamp::GetEpoch(TString mode)
+{
+// Provide the corresponding epoch value.
+// Via the input argument "mode" the user can specify the type of epoch
+//
+// mode = "B" ==> Besselian epoch
+// "J" ==> Julian epoch
+
+ Double_t e=0;
+ if (mode=="B" || mode=="b") e=GetBE();
+ if (mode=="J" || mode=="j") e=GetJE();
+ return e;
+}
+///////////////////////////////////////////////////////////////////////////
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff