caltask force workshop vlimant jean-rochlpnhe10 feb 2003 t42 algorithm dedicated webpage :
DESCRIPTION
cal_t42 Package using same frame as cal_nada Classes : Calt42 : container for cell lists Calt42Chunk : container for Calt42 object Calt42Reco : –does the cleaning and chunks managment. –Get the neighbourhood info from a Calt42Struct object which allows a linear algorithm complexity.TRANSCRIPT
CalTask Force Workshop
VLIMANT Jean-Roch LPNHE 10 feb 2003
T42 algorithmdedicated webpage :
http://www-d0.fnal.gov/~vlimant/noise-suppdescr/Description.html
PrincipaleImplementationEffect on dataTo come
T42Principale : reject isolated medium cells
Named after an algorithm used in H1
Select high signal cells (4 sigma) Keep their significant neighbours (2 sigma)
Thresholds to be tuned
What neighbours means
cal_t42 Packageusing same frame as cal_nada
Classes : Calt42 : container for cell lists Calt42Chunk : container for Calt42 object Calt42Reco :
– does the cleaning and chunks managment. – Get the neighbourhood info from a Calt42Struct object which
allows a linear algorithm complexity.
Calt42RecoCalCell
Is to be keptanyway ? KeepList
Is above firstthreshold ?
Is above secondthreshold ?
TrashList
AccessList
Alogirthm framework (part1)
Calt42RecoAccess List
cell
Is present ?KeepList
Alogirthm framework (part2)
Loop overneighbours
Calt42StructClass content
Objects– spine : array[81600] of structured object
Mapped to ieta, iphi, layer by :INDEX = iphi + 64( layer - 1 ) + 1088( ieta + 37 ) - 1
– Structured object fields sigma : tells the noise rms of the cell pointers to all possible neighbours within the array single pointer to be assigned to a CalCell available in data
lots of methods user-friendly method to read neighbourhood information from a text file
(rather than doing awfull, uncheckable code)
Calt42StructNeighbourhood information
http://www-d0.fnal.gov/~vlimant/noise-suppdescr/Description.html
How to check ?– Standalone executable return neighbours for a given cell
(exist as a method)– Check cell_files and pictures for exceptions descriptions
(webpage)– Check the code of the four executables (simple
algorithms)
Regular cells–normal–out of fine layers (3,4,5,6)–near fine layers (2,7)
Exceptions cells–Neighbours above or below splited into different layers–Intercryostat and nearby cells
Study effects on data Data sets
– Debugging (preliminary result ) with recoT_all_0000168619_mrg_116-143.raw_p13.04.00
– MET test (sophie) 1000 evts of recoT_all_0000168725_mrg_100-107.raw_p13.04.00
output : /work/coco-clued0/vlimant/TK2/runsophie/Recoanalyze.root
– W, Z tests (WZ) 10000 evts of WZskim-emStream-*-*.raw_p13.04.00
under the project name WZstreamTMBp13.04
Population reportoverall result for 10000 evts processing (WZ)
http://www-d0.fnal.gov/~vlimant/noise-suppps/WZ_plots/Pop_report_10000_WZ.ps
Before1815
After1265
At second(4)840
At first(0)1815
Population reportRegion result
237 138 (60) 55.6 17.9 (32) 7.87 0.23 (3) 762 601 (78) 600 435 (73) 56.5 6.2 (11) 54 36 (67) 43 28 (65)
before after (%)
Population reportRegion result
237 138 (60) : 40% 55.6 17.9 (32) : 38% 7.87 0.23 (3) : 60% 762 601 (78) : 31 % 600 435 (73) : 37 % 56.5 6.2 (11) : 41% 54 36 (67) : 42% 43 28 (65) : 12%
before after : % from neighbours below second threshlod
Isolated cells
Clustered cells
Isolation decreases and tightens by 10% EM fraction tightens by 25% Hmatrix8 decrease by 5%
EMIds increases by 10%
EM changes
MET increase (in mean)W transverse mass with more entries
MEx centered (- 30%) MEx made more even
fewer noise
MET changes
T42 conclusions Remains to do
Ultimatetly cross check neighbours Study thresholds for reasonnable loss
of cells More studies on effect on physics
– Rootuple with dedicated data block available, help is welcome