Difference between revisions of "Mattione sim-recon Code Documentation"
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(→DTrackHitSelector_ALT1::GetCDCHits()) |
(→DTrackHitSelector_ALT1::GetFDCHits()) |
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DTrackHitSelector_ALT1::GetFDCHits(): | DTrackHitSelector_ALT1::GetFDCHits(): | ||
- loop over DFDCPseudo objects: | - loop over DFDCPseudo objects: | ||
− | - calc | + | - calc track doca to hit |
− | - calc | + | - calc sigma (on track doca to hit), chisq, & FOM: sigma is relatively arbitrary |
− | - if FOM | + | - if FOM > minimum prob then keep the DCDCTrackHit |
- sort kept DFDCPseudo objects by ring & hit probability (reject hits in the same ring that are far away) | - sort kept DFDCPseudo objects by ring & hit probability (reject hits in the same ring that are far away) | ||
- output saved DFDCPseudo objects | - output saved DFDCPseudo objects |
Revision as of 17:34, 6 January 2012
Plugin-Independent Execution
hd_root
main():
- instantiates MyProcessor and DApplication
- MyProcessor inherits from JEventProcessor
- JEventProcessor basically empty/virtual, constructor only initializes a few conrol variables during instantiation
- MyProcessor constructor basically empty
- DApplication inherits from JApplication
- JApplication constructor sets up user signal instructions, mutexes, parses the command line, sets up the parameters in JParameterManager, etc.
- DApplication constructor instantiates the DEventSourceHDDMGenerator and DFactoryGenerator, and registers them with JApplication
- calls DApplication.Run(JEventProcessor) with the instantiated MyProcessor as the argument (DApplication.Run(JEventProcessor) is JApplication.Run(JEventProcessor))
- Calls DApplication.Init()
- Calls JApplication.Init()
- Attaches plugins (JEventProcessors), adds auto-activated factories (from the JParameterManager), calls JEventProcessor.init() for each processor (MyProcessor.init() creates the output root file)
- Checks to see if should use SSE instructions
- Launches threads (each thread calls JApplication.LaunchThread())
- Sends the main thread to sleep while the threads execute, wake up occassionally to check status, exits when done
- Exits
JApplication.LaunchThread()
JApplication.LaunchThread():
- Create JEventLoop with the instantiated JApplication object as the argument - JEventLoop constructor: - registers the JEventLoop with the JApplication object and its member JEvent object "event" - call JEventLoop.Loop() on the JEventLoop object - calls JEventLoop.OneEvent() in an infinite loop until that function tells it to quit the loop (that function loops over each event) - calls JEventLoop.Initialize() if not initialized: gets event processors and auto-activated factories from JApplication (which were listed in JParameterManager) - calls JEventLoop.ClearFactories(), which calls the .Reset() function of each factory - calls JApplication.NextEvent(JEvent), which grabs the next event from the event buffer - loops over JEventProcessors (for plugins, functionality is plugin-specific), calling these virtual functions: - JEventProcessors.brun() if it's a new run number: - if hd_root, calls MyProcessor.brun(): figures out which factories are needed, sets up their information (factory_info_t) in MyProcessor.fac_info - JEventProcessors.erun() if the run number changes: - if hd_root, calls MyProcessor.erun(): does nothing - JEventProcessors.evnt() for each event: - if hd_root, calls MyProcessor.evnt(): loops over all factories listed in MyProcessor.fac_info, grabs them from the JEventLoop, for each calls factory->GetNrows() - calls JEvent.FreeEvent() to free up the memory from this event - Exits
JEventLoop.Get(vector<const T*>)
JEventLoop.Get(vector<const T*>): call to retrieve data objects of type T with an associated factory (e.g. DChargedTrack, DPhysicsEvent)
- The JEventLoop.Get(vector<const T*>) function retrieves or generates the requested objects in this order: - If already generated, returns them. Else if present in input data file, retrieves them. Else generates them via the appropriate JFactory. - These objects are only generated once, and the generating factories retain ownership (only const pointers are returned) - To check if they were already generated, JEventLoop.Get(vector<const T*>) calls JEventLoop::GetFromFactory() - It grabs the associated JFactory. Note that all of the factories inherit from JFactory, which inherits from JFactory_base, which inherits from JEventProcessor - If its JFactory.evnt() method has already been called, then the JFactory.CopyFrom(vector<const T*>) method is called to just copy the already-generated information into the input vector. - To check if they are located in the source, JFactory.GetCheckSourceFirst() is called. If so, then JEventLoop.GetFromSource() is called to retrieve the input information. - To generate the data, the JFactory.Get(vector<const T*>) method is called. - If JFactory.evnt() has already been called, then it calls JFactory.CopyFrom(vector<const T*>) to copy the data into the input vector and returns. Else the function continues. - It calls JFactory.init() if it has not been called already. - It then calls JFactory.erun() and JFactory.brun() if appropriate. - Then JFactory.evnt() is called to generate the data, then it calls JFactory.CopyFrom(vector<const T*>) to copy the data into the input vector and returns.
Track Reconstruction
DTrackFitter::FindHitsAndFitTrack()
DTrackFitter::FindHitsAndFitTrack():
- call CorrectForELoss (WireBased fit only): assumes momentum from DTrackCandidate is at middle of track (avg), swims backwards to target center & increases momentum based on eloss - swim reference trajectory - get DTrackHitSelector_ALT1, all DCDCTrackHit objects, and all DFDCPseudo objects - call DTrackHitSelector::GetAllHits() with reference trajectory, DTrackHitSelector::fit_type_t (kHelical for kWireBased fit, or kWireBased for kTimeBased fit), DCDCTrackHit's, DFDCPseudo's - calls DTrackHitSelector::GetCDCHits - calls DTrackHitSelector_ALT1::GetCDCHits (with reference trajectory, DTrackHitSelector::fit_type_t, all DCDCTrackHit objects), sorts hits by ring, then stores them in the fitter - calls DTrackHitSelector::GetFDCHits - calls DTrackHitSelector_ALT1::GetFDCHits (with reference trajectory, DTrackHitSelector::fit_type_t, all DFDCPseudo objects), sorts hits by z, then stores them in the fitter - call FitTrack with position, momentum, q, mass, start time: sets DTrackFitter.input_params (a DKinematicData object) with these info, then calls DTrackFitterKalmanSIMD::FitTrack(void)
DTrackFitterKalmanSIMD::FitTrack(void)
DTrackFitterKalmanSIMD::FitTrack(void):
- calls ResetKalmanSIMD to reset data
- push back cdc hits into my_cdchits, fdc hits into my_fdchits
- for fdc: hit->dE=1e6*fdchit->dE;, hit->xres=hit->yres=1000.;
- start time (mT0) set from input, start time variance (mVarT0) fixed to 0.09
- calls SetSeed to set track parameters from input pos, mom, and charge
- Forward: x_, y_, z_, tx_ (px/pz), ty_ (py/pz), q_over_p_
- Central: phi_ (p.phi()), tanl_ (l = pi/2 - p.theta()), q_over_pt_
- set the mass (m_ratio = ELECTRON_MASS/MASS)
- call DTrackFitterKalmanSIMD::KalmanLoop() to do fit
- set fit results into DTrackFitter base class input_params (for subsequent output)
- charge, momentum, t0 (from cdc or fdc), position, mass
- also cov matrix: from "fcov" for forward params, else from "cov"
- sets cdchits_used_in_fit & fdchits_used_in_fit
DTrackFitterKalmanSIMD::KalmanForward()
DTrackFitterKalmanSIMD::KalmanForward():
- loop through track trajectory steps (stored in forward_traj) from the last step (largest z) to the first step - transform the state vector to the new step - project the error matrix from the previous step to the current step, and add the uncertainties due to eloss and multiple scattering - if any fdc hits (should always be true!!): - if no fdc hits associated with this step on the trajectory, continue - call fdc_y_variance() to calculate the variance on the track position in the coordinate along the wire (hard-coded, only hit energy dependent) - compute the residual: difference between the projected hit and the measured hit: 'Mdiff'. - if timebased tracking, use drift distance for Mdiff(0) too, not just doca. Also call fdc_drift_variance() to calculate the variance due to the drift (hard-coded func of drift-time) - compute the transformation matrix 'H' to transform between the hit position coordinates (u, v) to the track parameter coordinates (x, y) - if more than one fdc hit at this track step: - calculate the variance on the first fdc hit: transform covariance matrix 'C' using 'H' to u, v coordinates, add V - calculate the chi-squared of the hit residual - calculate the probability of the first fdc hit using the residual chi-squared - if chisq is too large, ignore the hit (outlier) (but still look at other fdc hits) - loop over other fdc hits, doing the same as the first fdc hit (calc residual, variance, chisq, probability; if chisq too high, ignore it) - loop over the hits whose chi-squared wasn't too large, compute the new state vector 'S' and covariance matrix 'C' using the hit probabilities to determine the weights (also set in fdc_updates) - else - calculate the variance on the hit: transform covariance matrix 'C' using 'H' to u, v coordinates, add V - calculate the chi-squared of the hit residual - if the chi-squared of the hit residual is too large, ignore the hit (outlier) (continue loop through track trajectory steps) - update the track state vector and covariance matrix - add the chi-squared of the hit residual to the total chi-squared (starts at zero) (track chi-squared = total chi-squared of the hit residuals) - else if any cdc hits: - NOT FINISHED!!!! (Can this EVER be called?? The only place that KalmanForward() is called is in KalmanLoop(), and only if there ARE fdc hits) - set x_, y_, and z_ to those of the final state vector (lowest z) - multiply chisq by the 'anneal_factor' which is 1 (but the fdc y & drift variances are already multiplied by this!!)
Hit Selection
DTrackHitSelector_ALT1::GetCDCHits()
DTrackHitSelector_ALT1::GetCDCHits():
- loop over DCDCTrackHit objects: - calc residual: diff btw "use reference trajectory to find DOCA of track to hit" and "use cell size & drift times (for TimeBased) to find "measured" distance" - calc sigma, chisq, & FOM: sigma is relatively arbitrary - if FOM > minimum prob then keep the DCDCTrackHit - sort kept DCDCTrackHit objects by ring & hit probability (reject hits in the same ring that are far away) - output saved DCDCTrackHit objects
DTrackHitSelector_ALT1::GetFDCHits()
DTrackHitSelector_ALT1::GetFDCHits():
- loop over DFDCPseudo objects: - calc track doca to hit - calc sigma (on track doca to hit), chisq, & FOM: sigma is relatively arbitrary - if FOM > minimum prob then keep the DCDCTrackHit - sort kept DFDCPseudo objects by ring & hit probability (reject hits in the same ring that are far away) - output saved DFDCPseudo objects