class AliITSUSeed: public AliExternalTrackParam

 def c-tor

 d-tor

 def c-tor

 def c-tor

 print seed info

 init seed from ESD track

 compare clusters accodring to specific mode

 compare clusters accodring to specific mode

 Propagate this track to the plane X=xk (cm) in the field "b" (kG)

 get ind-th cluster index

 Transform this track to the local coord. system rotated
 by angle "alpha" (rad) with respect to the global coord. system.

 calculate X and Y in the tracking frame of the track, corresponding to other X,Alpha tracking

 Estimate the chi2 of the space point "p" with the cov. matrix "cov"
 Store info needed for update and smoothing

 Update the track parameters with the measurement stored during GetPredictedChi2

 Prepare MBF smoothing auxiliary params for smoothing at prev. point:
 \hat{l_N} = 0
 \hat{L_N} = 0
 \tilde{l_j} = -H_j^T N_{j}^{-1} z_j + B_{j}^T \hat{l_j}
 \tilde{L_j} =  H_j^T N_{j}^{-1} H_j + B_j^T \hat{L_j} B_j
 \hat{l_j} = F_j^T \tilde{l_{j+1}}
 \hat{L_j} = F_j^T \tilde{L_{j+1}} F_j

 P_{j/N} = P_{j/j} - P_{j/j} \hat{L_j} P_{j/j}
 \hat{x_{j/N}} = \hat{x_{j/j}} - P_{j/j} \hat{l_j}

 N^-1 = fCovIYZ
 z = fResid
 B = I - K H
 H = {{1,0,0,0,0},{0,1,0,0,0}}

 calc. \tilde{l_j}

 product of symmetric matrices A*B*A

 check if the full branch containes a fake cluster

 fill cl.id's in the array. The clusters of layer L will be set at slots
 clID[2L] (and clID[2L+1] if there is an extra cluster).