//
// Note :
// ------
-// Vectors (v), Errors (e) and reference frames (f) are specified via
-// SetVector(Float_t* v,TString f)
-// SetErrors(Float_t* e,TString f)
+// Vectors (v), Errors (e), reference frames (f) and angular units (u)
+// are specified via
+// SetVector(Float_t* v,TString f,TString u)
+// SetErrors(Float_t* e,TString f,TString u)
// under the following conventions :
//
-// f="car" ==> 3-vector part of v in Cartesian coordinates (x,y,z)
-// f="sph" ==> 3-vector part of v in Spherical coordinates (r,theta,phi)
-// f="cyl" ==> 3-vector part of v in Cylindrical coordinates (rho,phi,z)
+// f="car" ==> v in Cartesian coordinates (x,y,z)
+// f="sph" ==> v in Spherical coordinates (r,theta,phi)
+// f="cyl" ==> v in Cylindrical coordinates (rho,phi,z)
//
-// All angles are in radians.
+// u="rad" ==> angles in radians
+// u="deg" ==> angles in degrees
+//
+// The "f" and "u" facilities only serve as a convenient user interface.
+// Internally the actual storage of the various components is performed
+// in a unique way. This allows setting/retrieval of vector components in a
+// user selected frame/unit convention at any time.
//
// Example :
// ---------
// a.SetVector(v,"car");
//
// Float_t vec[4];
-// a.GetVector(vec,"sph");
+// a.GetVector(vec,"sph","deg");
//
// Ali4Vector b;
// Float_t v2[4]={33,6,-18,2};
SetScalarError(0);
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::SetVector(Double_t* v,TString f)
+void Ali4Vector::SetVector(Double_t* v,TString f,TString u)
{
// Store vector according to reference frame f.
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+//
// All errors are initialised to 0.
+//
// Scalar mode is automatically selected.
// The error on scalar result operations is reset to 0.
+
fScalar=1;
Double_t a[3];
for (Int_t i=0; i<3; i++)
a[i]=v[i+1];
}
fV0=v[0];
- fV.SetVector(a,f);
+ fV.SetVector(a,f,u);
fV2=pow(fV0,2)-fV.Dot(fV);
fDv2=0;
fDv0=0;
fDresult=0;
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::GetVector(Double_t* v,TString f)
+void Ali4Vector::GetVector(Double_t* v,TString f,TString u)
{
// Provide 4-vector components according to reference frame f
// and according to the current mode.
// Scalar mode : The scalar part is directly returned via v[0].
// Invariant mode : The scalar part is re-calculated via the value
// of the Lorentz invariant and then returned via v[0].
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+
if (fScalar)
{
v[0]=fV0;
v[0]=sqrt(fV.Dot(fV)+fV2);
}
Double_t a[3];
- fV.GetVector(a,f);
+ fV.GetVector(a,f,u);
for (Int_t i=0; i<3; i++)
{
v[i+1]=a[i];
}
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::SetVector(Float_t* v,TString f)
+void Ali4Vector::SetVector(Float_t* v,TString f,TString u)
{
// Store vector according to reference frame f.
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+//
// All errors are initialised to 0.
+//
// Scalar mode is automatically selected.
// The error on scalar result operations is reset to 0.
+
Double_t vec[4];
for (Int_t i=0; i<4; i++)
{
vec[i]=v[i];
}
- SetVector(vec,f);
+ SetVector(vec,f,u);
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::GetVector(Float_t* v,TString f)
+void Ali4Vector::GetVector(Float_t* v,TString f,TString u)
{
// Provide 4-vector components according to reference frame f
// and according to the current mode.
// Scalar mode : The scalar part is directly returned via v[0].
// Invariant mode : The scalar part is re-calculated via the value
// of the Lorentz invariant and then returned via v[0].
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+
Double_t vec[4];
- GetVector(vec,f);
+ GetVector(vec,f,u);
for (Int_t i=0; i<4; i++)
{
v[i]=vec[i];
}
}
///////////////////////////////////////////////////////////////////////////
-Double_t Ali4Vector::GetResultError()
+Double_t Ali4Vector::GetResultError() const
{
// Provide the error on the result of an operation yielding a scalar
// E.g. GetScalar(), GetInvariant() or Dot()
}
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::Set3Vector(Double_t* v,TString f)
+void Ali4Vector::Set3Vector(Double_t* v,TString f,TString u)
{
// Set the 3-vector part according to reference frame f
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+//
// The errors on the vector part are initialised to 0
+//
// Scalar mode : The scalar part and its error are not modified,
// the Lorentz invariantand its error are re-calculated.
// Invariant mode : The Lorentz invariant and its error are not modified,
// the scalar part and its error are re-calculated.
// The error on scalar result operations is reset to 0.
+
Double_t a[3];
for (Int_t i=0; i<3; i++)
{
a[i]=v[i];
}
- fV.SetVector(a,f);
+ fV.SetVector(a,f,u);
if (fScalar)
{
}
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::Set3Vector(Float_t* v,TString f)
+void Ali4Vector::Set3Vector(Float_t* v,TString f,TString u)
{
// Set the 3-vector part according to reference frame f
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+//
// The errors on the vector part are initialised to 0
// The Lorentz invariant is not modified
// The error on scalar result operations is reset to 0.
+
Double_t vec[3];
for (Int_t i=0; i<3; i++)
{
vec[i]=v[i];
}
- Set3Vector(vec,f);
+ Set3Vector(vec,f,u);
}
///////////////////////////////////////////////////////////////////////////
void Ali4Vector::SetInvariant(Double_t v2,Double_t dv2)
}
}
///////////////////////////////////////////////////////////////////////////
-Ali3Vector Ali4Vector::Get3Vector()
+Ali3Vector Ali4Vector::Get3Vector() const
{
// Provide the 3-vector part
return fV;
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::SetErrors(Double_t* e,TString f)
+void Ali4Vector::SetErrors(Double_t* e,TString f,TString u)
{
// Store errors for vector v^i according to reference frame f
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+//
// If in scalar mode, update error on the invariant accordingly.
// The error on scalar result operations is reset to 0.
+
Double_t a[3];
for (Int_t i=0; i<3; i++)
{
a[i]=e[i+1];
}
SetScalarError(e[0]);
- fV.SetErrors(a,f);
+ fV.SetErrors(a,f,u);
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::SetErrors(Float_t* e,TString f)
+void Ali4Vector::SetErrors(Float_t* e,TString f,TString u)
{
// Store errors for vector v^i according to reference frame f
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+//
// If in scalar mode, update error on the invariant accordingly.
// The error on scalar result operations is reset to 0.
+
Double_t a[4];
for (Int_t i=0; i<4; i++)
{
a[i]=e[i];
}
- SetErrors(a,f);
+ SetErrors(a,f,u);
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::GetErrors(Double_t* e,TString f)
+void Ali4Vector::GetErrors(Double_t* e,TString f,TString u)
{
// Provide errors for vector v^i according to reference frame f
// and according to the current mode.
// Scalar mode : The error on the scalar part is directly returned via e[0].
// Invariant mode : The error on the scalar part is re-calculated via the error
// value on the Lorentz invariant and then returned via e[0].
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+
Double_t a[3];
- fV.GetErrors(a,f);
+ fV.GetErrors(a,f,u);
// Dummy invokation of GetScalar to obtain automatic proper error determination
e[0]=GetScalar();
}
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::GetErrors(Float_t* e,TString f)
+void Ali4Vector::GetErrors(Float_t* e,TString f,TString u)
{
// Provide errors for vector v^i according to reference frame f
// and according to the current mode.
// Scalar mode : The error on the scalar part is directly returned via e[0].
// Invariant mode : The error on the scalar part is re-calculated via the error
// value on the Lorentz invariant and then returned via e[0].
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+
Double_t a[4];
- GetErrors(a,f);
+ GetErrors(a,f,u);
for (Int_t i=0; i<4; i++)
{
e[i]=a[i];
}
}
///////////////////////////////////////////////////////////////////////////
-void Ali4Vector::Data(TString f)
+void Ali4Vector::Data(TString f,TString u)
{
// Print contravariant vector components and errors according to
// reference frame f and according to the current mode.
// Scalar mode : The scalar part and its error are directly returned.
// Invariant mode : The scalar part and its error are re-calculated via the
// value (and error) of the Lorentz invariant.
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The defaults are f="car" and u="rad".
if (f=="car" || f=="sph" || f=="cyl")
{
Double_t vec[4],err[4];
- GetVector(vec,f);
- GetErrors(err,f);
+ GetVector(vec,f,u);
+ GetErrors(err,f,u);
Double_t inv=GetInvariant();
Double_t dinv=GetResultError();
- cout << " Contravariant vector in " << f.Data() << " coordinates : "
+ cout << " Contravariant vector in " << f.Data() << " (" << u.Data() << ") coordinates : "
<< vec[0] << " " << vec[1] << " " << vec[2] << " " << vec[3] << endl;
- cout << " ------------- Errors in " << f.Data() << " coordinates : "
+ cout << " ------------- Errors in " << f.Data() << " (" << u.Data() << ") coordinates : "
<< err[0] << " " << err[1] << " " << err[2] << " " << err[3] << endl;
cout << " --- Lorentz invariant (v^i*v_i) : " << inv << " error : " << dinv << endl;
}
}
}
///////////////////////////////////////////////////////////////////////////
-Int_t Ali4Vector::GetScalarFlag()
+Int_t Ali4Vector::GetScalarFlag() const
{
// Provide the value of the fScalar flag (for internal use only).
return fScalar;
}
///////////////////////////////////////////////////////////////////////////
-Ali3Vector Ali4Vector::GetVecTrans()
+Ali3Vector Ali4Vector::GetVecTrans() const
{
// Provide the transverse vector part w.r.t. z-axis.
// Error propagation is performed automatically
return fV.GetVecTrans();
}
///////////////////////////////////////////////////////////////////////////
-Ali3Vector Ali4Vector::GetVecLong()
+Ali3Vector Ali4Vector::GetVecLong() const
{
// Provide the longitudinal vector part w.r.t. z-axis.
// Error propagation is performed automatically
return eta;
}
///////////////////////////////////////////////////////////////////////////
+Ali3Vector Ali4Vector::GetBetaVector() const
+{
+// Provide the beta 3-vector corresponding to this 4-vector.
+ Ali3Vector beta;
+ if (fabs(fV0)>0.) beta=fV/fV0;
+ if (fabs(fDv0)>0.)
+ {
+ Double_t vecv[3],errv[3],errb[3];
+ Double_t sqerr=0;
+ fV.GetVector(vecv,"car");
+ fV.GetErrors(errv,"car");
+ for (Int_t i=0; i<3; i++)
+ {
+ sqerr=pow((errv[i]/fV0),2)+pow((vecv[i]*fDv0/(fV0*fV0)),2);
+ errb[i]=sqrt(sqerr);
+ }
+ beta.SetErrors(errb,"car");
+ }
+ return beta;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t Ali4Vector::GetBeta()
+{
+// Provide the beta value (i.e. v/c) corresponding to this 4-vector.
+ Ali3Vector beta=GetBetaVector();
+ Double_t val=beta.GetNorm();
+ fDresult=beta.GetResultError();
+ return val;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t Ali4Vector::GetGamma()
+{
+// Provide the Lorentz gamma factor corresponding to this 4-vector.
+// In case the gamma factor is infinite a value of -1 is returned.
+ Double_t gamma=-1;
+ fDresult=0;
+ Double_t inv=sqrt(fabs(fV2));
+ if (inv>0.)
+ {
+ Double_t dinv=fDv2/(2.*inv);
+ gamma=fV0/inv;
+ Double_t sqerr=pow((fDv0/inv),2)+pow((fV0*dinv/fV2),2);
+ fDresult=sqrt(sqerr);
+ }
+ return gamma;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t Ali4Vector::GetX(Int_t i,TString f,TString u)
+{
+// Provide i-th vector component according to reference frame f.
+//
+// The string argument "u" allows to choose between different angular units
+// in case e.g. a spherical frame is selected.
+// u = "rad" : angles provided in radians
+// "deg" : angles provided in degrees
+//
+// The default is u="rad".
+//
+// The vector components are addressed via the generic x0,x1,x2,x3 notation.
+// So, i=0 denotes the scalar component and i=1 denotes the first 3-vector component.
+// The error on the selected component can be obtained via the
+// usual GetResultError() facility.
+
+ fDresult=0;
+
+ if (i<0 || i>3) return 0;
+
+ Double_t x=0;
+
+ if (i==0)
+ {
+ x=GetScalar();
+ }
+ else
+ {
+ x=fV.GetX(i,f,u);
+ fDresult=fV.GetResultError();
+ }
+
+ return x;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t Ali4Vector::GetOpeningAngle(Ali4Vector& q,TString u)
+{
+// Provide the opening angle between 3-vector parts with 4-vector q.
+// The string argument "u" allows to choose between different output units.
+// u = "rad" : opening angle provided in radians
+// "deg" : opening angle provided in degrees
+//
+// The default is u="rad".
+
+ Ali3Vector v1=fV;
+ Ali3Vector v2=q.Get3Vector();
+
+ Double_t ang=v1.GetOpeningAngle(v2,u);
+ fDresult=v1.GetResultError();
+
+ return ang;
+}
+///////////////////////////////////////////////////////////////////////////
+Double_t Ali4Vector::GetOpeningAngle(Ali3Vector& q,TString u)
+{
+// Provide the opening angle between the 3-vector part and 3-vector q.
+// The string argument "u" allows to choose between different output units.
+// u = "rad" : opening angle provided in radians
+// "deg" : opening angle provided in degrees
+//
+// The default is u="rad".
+
+ Ali3Vector v1=fV;
+
+ Double_t ang=v1.GetOpeningAngle(q,u);
+ fDresult=v1.GetResultError();
+
+ return ang;
+}
+///////////////////////////////////////////////////////////////////////////