BfldMapRect2d class Reference

00050    : BfldMap(grid,variant), fReadOk(kFALSE)
00051 {
00052    // read in a Map
00053 
00054    // strip off "-" sign if necessary
00055    Int_t varabs = TMath::Abs(variant);
00056 
00057    MSG("Bfld",Msg::kInfo) << "BfldMapRect2d ctor map " << varabs << endl;
00058 
00059    char string[255];
00060 
00061    // format and expand file name
00062    sprintf(string,"$BMAPPATH/bfld_%3d.dat",varabs);
00063    fFilename = string;
00064    gSystem->ExpandPathName(fFilename);
00065 
00066    // open the file for reading
00067    ifstream from;
00068    from.open(fFilename,ios::in);
00069    if (!from) {
00070       MSG("Bfld",Msg::kError) << "can not open input file: '" 
00071                               << fFilename <<"'"<< endl;
00072       return;
00073    }
00074 
00075    // read in the header line
00076    from.getline(string,sizeof(string),'\n');
00077    fHeader = string;
00078 
00079    
00080    MSG("Bfld",Msg::kInfo) << "read file: " << fFilename << endl;
00081    MSG("Bfld",Msg::kInfo) << "   header: " << fHeader << endl;
00082 
00083    from >> fX0 >> fDx >> fNx >> fY0 >> fDy >> fNy;
00084    // lengths read in from map files are in cm, convert to base units
00085    fX0 *= Munits::cm;
00086    fDx *= Munits::cm;
00087    fY0 *= Munits::cm;
00088    fDy *= Munits::cm;
00089 
00090 
00091    MSG("Bfld",Msg::kInfo) 
00092       << " x0 " << fX0 << " dx " << fDx << " nx " << fNx 
00093       << " y0 " << fY0 << " dy " << fDy << " ny " << fNy << endl;
00094 
00095    // read in remainder of the line for any quadflags
00096    from.getline(string,sizeof(string),'\n');
00097    TString quads = string;
00098 
00099    // first 19 characters are useless junk (z0,dz,nz)
00100    // replace "x" with " "
00101    quads = quads.Remove(0,19);
00102    quads = quads.ReplaceAll("x"," ");
00103    // quads should be of the form ' 00 00 00 00  FNAL2'
00104 
00105    fFileForm = 0;
00106    if (quads.Contains("FNAL"))  fFileForm = 1;
00107    if (quads.Contains("FNAL2")) fFileForm = 2;
00108    MSG("Bfld",Msg::kInfo) << "fileform " << fFileForm << endl;
00109 
00110    // remove any "FNAL" flag
00111    if (quads.Length() > 12) quads = quads.Remove(12);
00112 
00113    // scan the remaining part for the quad flags
00114    if (quads.Length() > 0) {
00115       sscanf(quads,"%3d%3d%3d%3d",
00116              fQuadFlags,fQuadFlags+1,fQuadFlags+2,fQuadFlags+3);
00117    } else {
00118       MSG("Bfld",Msg::kInfo) << "no quads info - use defaults" << endl;
00119       fQuadFlags[0] = 0;
00120       fQuadFlags[1] = 2;
00121       fQuadFlags[2] = 3;
00122       fQuadFlags[3] = 1;
00123    }
00124 
00125    // if x0=0,y0=0 assume map only has one quadrant 
00126    fQuadrant = ( 0 == fX0 && 0 == fY0 );
00127 
00128    MSG("Bfld",Msg::kInfo) << "quadflags (" 
00129                           << fQuadFlags[0] << "," 
00130                           << fQuadFlags[1] << "," 
00131                           << fQuadFlags[2] << "," 
00132                           << fQuadFlags[3] << ")  use them " 
00133                           << (fQuadrant ? "'true'" : "'false'") << endl;
00134 
00135    // allocate a container
00136    fFieldVectors = new TClonesArray("TVector3",fNx*fNy);
00137 
00138    Int_t   ii, indx;
00139    Float_t x,y,z;
00140    Float_t bx,by,bz,bmag;
00141 
00142    const Float_t GaussToKGauss = 0.001;
00143    const Float_t TeslaToKGauss = 10.;
00144 
00145    // start reading the file
00146    for (Int_t i=0; i < fNx*fNy; i++) {
00147 
00148       switch (fFileForm) {
00149       case 0:
00150          from >> x >> y >> z >> bx >> by >> bz >> bmag;
00151          // LLNL maps were in gauss ... need kGauss
00152          bx   = bx   * GaussToKGauss;
00153          by   = by   * GaussToKGauss;
00154          bz   = bz   * GaussToKGauss;
00155          bmag = bmag * GaussToKGauss;
00156          break;
00157       case 1:
00158          from >> ii >> x >> y >> bx >> by;
00159          // FNAL (version 1) maps were in Tesla
00160          bx   = bx   * TeslaToKGauss;
00161          by   = by   * TeslaToKGauss;
00162          bz   = 0.0;
00163          break;
00164       case 2:
00165          from >> x >> y >> z >> bx >> by >> bz >> bmag;
00166          // FNAL (version 2) maps were in Tesla
00167          bx   = bx   * TeslaToKGauss;
00168          by   = by   * TeslaToKGauss;
00169          bz   = bz   * TeslaToKGauss;
00170          bmag = bmag * TeslaToKGauss;
00171          break;
00172       default:
00173          MSG("Bfld",Msg::kFatal) << " bad FileForm " << fFileForm << endl;
00174          break;
00175       }
00176       // the above puts field values in kGauss
00177       // convert them to base units
00178       bx   *= Munits::kilogauss;
00179       by   *= Munits::kilogauss;
00180       bz   *= Munits::kilogauss;
00181       bmag *= Munits::kilogauss;
00182       // positions read in are given in cm
00183       x    *= Munits::cm;
00184       y    *= Munits::cm;
00185       z    *= Munits::cm;
00186 
00187       // all the maps aren't in consistent order (ascending/descending x,y)
00188       // so we have to actually interpret the (x,y) values to determine 
00189       // the array index.
00190       // we'll put them in the array in a way that we can lookup 
00191       // based on fX0,fDx,fNx,fY0,fDy,fNy
00192 
00193       indx = LowerLeftGenerator(x,y);
00194 
00195       // create new TVector3 and put it in the TClonesArray
00196       // what a crazy syntax!
00197       new((*fFieldVectors)[indx]) TVector3(bx,by,bz);
00198 
00199 #ifdef BLAHBLAH
00200       // one *might* think of using [i] rather than [indx]
00201       if (indx != i &&  i < 2*fNx ) {
00202          MSG("Bfld",Msg::kWarning) << " i " << i << " indx " << indx
00203                                    << " (" << x << "," << y << ")" << endl;
00204       }
00205 #endif
00206 
00207 
00208    }
00209 
00210    MSG("Bfld",Msg::kInfo) << "BfldMapRect2d file read in" << endl;
00211 
00212    fReadOk = kTRUE;
00213 }

Public Methods
	BfldMapRect2d ()
	BfldMapRect2d (BfldGrid::Grid_t grid, Int_t variant)
virtual	~BfldMapRect2d ()
virtual TVector3	GetBField (Int_t generator)
virtual TVector3	GetRawField (Int_t generator)
virtual void	SetMesh (BfldMesh *mesh)
Float_t	GetX0 ()
Float_t	GetY0 ()
Float_t	GetDx ()
Float_t	GetDy ()
Int_t	GetNx ()
Int_t	GetNy ()
Int_t *	GetQuadFlags ()
virtual Int_t	IndicesToGenerator (Int_t ix, Int_t iy)
virtual void	GeneratorToIndices (Int_t gen, Int_t &ix, Int_t &iy)
virtual Int_t	LowerLeftGenerator (Float_t x, Float_t y)
virtual Int_t	LowerLeftGenerator (TVector3 xyz)
virtual Int_t	NeighborGenerator (Int_t gen, Int_t dnx, Int_t dny)
Protected Attributes
Bool_t	fReadOk
TString	fFilename
TString	fHeader
Float_t	fX0
Float_t	fDx
Int_t	fNx
Float_t	fY0
Float_t	fDy
Int_t	fNy
Bool_t	fQuadrant
Int_t	fQuadFlags [4]
Int_t	fFileForm

BfldMapRect2d Class Reference

Public Methods

Protected Attributes

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation