class AliITSsegmentationSPD: public AliITSsegmentation

 Default constructor

 Get column number for each z-coordinate taking into account the
 extra pixels in z direction assuming 300 micron sized pixels.

 same comments as above
 Get z-coordinate for each colunm number

 returns Z pixel pitch for 300 micron pixels.

 hard-wired - keep it like this till we can parametrise
 and get rid of AliITSgeomSPD425
 Get column number for each z-coordinate taking into account the
 extra pixels in z direction

 same comments as above
 Get z-coordinate for each colunm number

 Get pitch size in z direction for each colunm

 protected method. copy this to obj

 = operator

 Fills the array of pixel sizes in x, microns
 The input array x must have 256 elements.

 Initialize infromation for 6 read out chip 300X50 micron pixel SPD
 detectors. This chip is 150 microns thick by 1.28 cm in x by 8.37 cm
 long. It has 256  50 micron pixels in x and 279 300 micron size
 pixels in z.

 Initialize information for 5 read out chip 425X50 micron pixel SPD
 detectors (ladder).
 Each readout chip is 150 micron thick.
 The ladder sensor is 200 micron thick by 1.28 cm in x by 6.96 cm in z.
 It has 256 50 micron pixels in x and 160 mostly 425 micron pixels in z.
 The two pixels at boundary between two adjacent readout chips are
 625 micron long.

 for SPD this function should be used ONLY when a beam test setup
 configuration is studied

returs x pixel pitch for a give pixel

 returns z pixel pitch for a give pixel

  Returns pixel coordinates (ix,iz) for given real local coordinates (x,z)

  local transformation of real local coordinates (x,z)

 Transform from pixel to real local coordinates

 Transformation from Geant detector centered local coordinates (cm) to
 Pixel cell numbers ix and iz.
 Input:
    Float_t   x        detector local coordinate x in cm with respect to
                       the center of the sensitive volume.
    Float_t   z        detector local coordinate z in cm with respect to
                       the center of the sensitive volulme.
 Output:
    Int_t    ix        detector x cell coordinate. Has the range
                       0<=ix<fNpx.
    Int_t    iz        detector z cell coordinate. Has the range
                       0<=iz<fNpz.
 Return:
   kTRUE if point x,z is inside sensitive volume, kFALSE otherwise.
   A value of -1 for ix or iz indecates that this point is outside of the
   detector segmentation as defined.

 Transformation from Detector cell coordiantes to Geant detector centerd
 local coordinates (cm).
 Input:
 Int_t    ix        detector x cell coordinate. Has the range 0<=ix<fNpx.
 Int_t    iz        detector z cell coordinate. Has the range 0<=iz<fNpz.
 Output:
 Float_t   x        detector local coordinate x in cm with respect to the
                    center of the sensitive volume.
 Float_t   z        detector local coordinate z in cm with respect to the
                    center of the sensitive volulme.
 If ix and or iz is outside of the segmentation range a value of -0.5*Dx()
 or -0.5*Dz() is returned.

 Transformation from Detector cell coordiantes to Geant detector centerd
 local coordinates (cm).
 Input:
 Int_t    ix        detector x cell coordinate. Has the range 0<=ix<fNpx.
 Int_t    iz        detector z cell coordinate. Has the range 0<=iz<fNpz.
 Output:
 Double_t   xl       detector local coordinate cell lower bounds x in cm
                    with respect to the center of the sensitive volume.
 Double_t   xu       detector local coordinate cell upper bounds x in cm
                    with respect to the center of the sensitive volume.
 Double_t   zl       detector local coordinate lower bounds z in cm with
                    respect to the center of the sensitive volulme.
 Double_t   zu       detector local coordinate upper bounds z in cm with
                    respect to the center of the sensitive volulme.
 If ix and or iz is outside of the segmentation range a value of -0.5*Dx()
 and -0.5*Dx() or -0.5*Dz() and -0.5*Dz() are returned.

 returns chip number (in range 0-4) starting from channel number

 returns chip number (in range 0-4) starting from local coordinates

 returns the number of chips containing a road defined by given local coordinate limits

 Returns the maximum number of cells (digits) posible

 Maximum number of Pixels in x

 Maximum number of Pixels in z

 Print default parameters (static const data members, if any)