MuonCSCChamberResidual.cc

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/* 
 * $Id: $
 */

#include "Alignment/MuonAlignmentAlgorithms/interface/MuonCSCChamberResidual.h"
#include "Geometry/CSCGeometry/interface/CSCGeometry.h"

#include "TrackingTools/Records/interface/TrackingComponentsRecord.h"
#include "TrackingTools/GeomPropagators/interface/Propagator.h"

MuonCSCChamberResidual::MuonCSCChamberResidual(edm::ESHandle<GlobalTrackingGeometry> globalGeometry, AlignableNavigator *navigator,
        DetId chamberId, AlignableDetOrUnitPtr chamberAlignable)
: MuonHitsChamberResidual(globalGeometry, navigator, chamberId, chamberAlignable)
{
    m_type = MuonChamberResidual::kCSC;
    align::GlobalVector zDirection(0., 0., 1.);
    m_sign = m_globalGeometry->idToDet(m_chamberId)->toLocal(zDirection).z() > 0. ? 1. : -1.;
}


void MuonCSCChamberResidual::addResidual(edm::ESHandle<Propagator> prop, const TrajectoryStateOnSurface *tsos, const TrackingRecHit *hit, double chamber_width, double chamber_length)
{
    bool m_debug = false;

    if (m_debug) std::cout << "MuonCSCChamberResidual::addResidual 1" << std::endl;
    DetId id = hit->geographicalId();
    if (m_debug) std::cout << "MuonCSCChamberResidual::addResidual 2" << std::endl;
    const CSCGeometry *cscGeometry = dynamic_cast<const CSCGeometry*>(m_globalGeometry->slaveGeometry(id));
    if (m_debug) std::cout << "MuonCSCChamberResidual::addResidual 3" << std::endl;
    assert(cscGeometry);

    if (m_debug) {
        std::cout << " MuonCSCChamberResidual hit->localPosition() x: " <<  hit->localPosition().x() << " tsos->localPosition() x: " << tsos->localPosition().x() << std::endl;
        std::cout << "                        hit->localPosition() y: " <<  hit->localPosition().y() << " tsos->localPosition() y: " << tsos->localPosition().y() << std::endl;
        std::cout << "                        hit->localPosition() z: " <<  hit->localPosition().z() << " tsos->localPosition() z: " << tsos->localPosition().z() << std::endl;
    }

    // hit->localPosition() is coordinate in local system of LAYER. Transfer it to coordiante in local system of chamber
    align::LocalPoint hitChamberPos = m_chamberAlignable->surface().toLocal(m_globalGeometry->idToDet(id)->toGlobal(hit->localPosition()));
    // TSOS->localPosition() is given in local system of CHAMBER (for segment-based reconstruction)
    //  align::LocalPoint tsosChamberPos = tsos->localPosition();
    align::LocalPoint tsosChamberPos = m_chamberAlignable->surface().toLocal(m_globalGeometry->idToDet(id)->toGlobal(tsos->localPosition()));

    int strip = cscGeometry->layer(id)->geometry()->nearestStrip(hit->localPosition());
    double angle = cscGeometry->layer(id)->geometry()->stripAngle(strip) - M_PI/2.;
    double sinAngle = sin(angle);
    double cosAngle = cos(angle);

    double residual = cosAngle * (tsosChamberPos.x() - hitChamberPos.x()) + sinAngle * (tsosChamberPos.y() - hitChamberPos.y());  // yes, that's +sin()

    if (m_debug) std::cout << " MuonCSCChamberResidual residual: " << residual << std::endl;

    double xx = hit->localPositionError().xx();
    double xy = hit->localPositionError().xy();
    double yy = hit->localPositionError().yy();
    double weight = 1. / (xx*cosAngle*cosAngle + 2.*xy*sinAngle*cosAngle + yy*sinAngle*sinAngle);

    double layerPosition = tsosChamberPos.z();  // the layer's position in the chamber's coordinate system
    double layerHitPos = hitChamberPos.z();

    m_numHits++;

    // "x" is the layerPosition, "y" is the residual (this is a linear fit to residual versus layerPosition)
    m_residual_1 += weight;
    m_residual_x += weight * layerPosition;
    m_residual_y += weight * residual;
    m_residual_xx += weight * layerPosition * layerPosition;
    m_residual_xy += weight * layerPosition * residual;

    // "x" is the layerPosition, "y" is chamberx (this is a linear fit to chamberx versus layerPosition)
    m_trackx_1 += weight;
    m_trackx_x += weight * layerPosition;
    m_trackx_y += weight * tsosChamberPos.x();
    m_trackx_xx += weight * layerPosition * layerPosition;
    m_trackx_xy += weight * layerPosition * tsosChamberPos.x();

    // "x" is the layerPosition, "y" is chambery (this is a linear fit to chambery versus layerPosition)
    m_tracky_1 += weight;
    m_tracky_x += weight * layerPosition;
    m_tracky_y += weight * tsosChamberPos.y();
    m_tracky_xx += weight * layerPosition * layerPosition;
    m_tracky_xy += weight * layerPosition * tsosChamberPos.y();

    m_hitx_1 += weight;
    m_hitx_x += weight * layerHitPos;
    m_hitx_y += weight * hitChamberPos.x();
    m_hitx_xx += weight * layerHitPos * layerHitPos;
    m_hitx_xy += weight * layerHitPos * hitChamberPos.x();

    m_hity_1 += weight;
    m_hity_x += weight * layerHitPos;
    m_hity_y += weight * hitChamberPos.y();
    m_hity_xx += weight * layerHitPos * layerHitPos;
    m_hity_xy += weight * layerHitPos * hitChamberPos.y();

    m_localIDs.push_back(id);
    m_localResids.push_back(residual); // FIXME Check if this method is needed
    m_individual_x.push_back(layerPosition);
    m_individual_y.push_back(residual);
    m_individual_weight.push_back(weight);

    if (m_numHits>1) segment_fit();
}