# Presentation: 811675

## Items for restart of run 

- Unify .gcon and .ifit (gcon V3.0 (fcon?))
- Got more comments/did some format changes
- Code written to produce it & convert existing files
- 0123X_wide.gcon available in new format in cvs
- Need to _modify mapset format_
- Cold-start (and all rest) _needs to read new format_
- Integrate slightly modified gconconv inside coldstart
- More compact pattern files (simple, but not yet)
- DataBase it ! ?
- Support for nonlinearity correction
- Hooks provided in new gcon
- Implement after approval.
- Mixed-layers support
- gcon/patt generation already available
- New: improve constants by orthogonalization

## 
Requirements for new fit constant file:
wedge-oriented, allows to specify up to the 150 constants sets. 
allow multiple layer combinations in the same wedge
allow mix&match of different layers in the same file without having to worry about shifts
must be readable and easily interpreted 
avoid elements that are too specifically related to details in the TF structure
 trasformation from this file to the memory content must be unique (=> no FP) 
 allows svtsim/svtmon to know the units of what is stored in SVTD.
 Remove magic numbers inside code
Extra features:
Contains just the right amount of information for each constants: units chosen make exact integers sufficient for the required precision
Allows to see easily where precision is lost

- Requirements for new fit constant file:
- wedge-oriented, allows to specify up to the 150 constants sets.
- allow multiple layer combinations in the same wedge
- allow mix&match of different layers in the same file without having to worry about shifts
- must be readable and easily interpreted
- avoid elements that are too specifically related to details in the TF structure
-  trasformation from this file to the memory content must be unique (=> no FP)
-  allows svtsim/svtmon to know the units of what is stored in SVTD.
-  Remove magic numbers inside code
- Extra features:
- Contains just the right amount of information for each constants: _units chosen make exact integers sufficient for the required precision_
- Allows to see easily where precision is lost

## //

- //There is one file per SVT wedge (1/72). Each file can contain several blocks,
- //one for every supported layer combination (and possibly longhit mask).
- //EACH block has the format that follows (yes, even the version number is replicated):
- Version 3.0
- //NPARFIT(always 3, for future expansion)
- 3
- 0 00 ! Zin, Long cluster info - input in the TF table
- 013F ! List of *physical* layer numbers (see http://www.pi.infn.it/~punzi/SVT_numbering.txt).
- 		 Their number is referred to as NLAYERS below.
- // List of NLAYERS step sizes (floats).
- step1 step2 step3 ...
- // List of the widths of bit-fields for each layer
- w1 w2 w3 ...
- // To convert the input x from CDF units to the units used by the constants stored below
- // one needs to do: x/(step*2^w). That is, the gcon are in units of total widths of input x,
- // and specified steps for the output
- // 1*(float) + NLAYERS*(int) + 1*(int). Each step converts the output parameter into CDF units
- cstep Vc Cc
- dstep Vd Cd
- fstep Vf Cf
- //kernel: 1*float+NLAYERS*(int)+1*(int)
- k0step kern0 kav0
- k1step kern1 kav1
- k2step kern2 kav2
- //This final constant is the conversion factor to get an actual chi-square.
- chi2step

## Version 3	! File format version number

- //NPAR
- 3
- //Zin, longhit_mask
- 0 00
- //Layers
- 1234F
- 3.750000e-04 3.875000e-04 3.750000e-04 3.750000e-04 2.727077e-03 4.408198e-05
- 14 14 14 14 12 7
- 1.172e-05 869 127  -517 -528 9414 17 226
- 1.000e-03 7288 3569 -970 -3705 2834 15 112
- 7.670e-04 -1413 -397 713 1124 -1374 -10 -393
- //Kernel
- 5.000e-01 238 -3102 6644 -3882 403 3 -69
- 5.000e-01 4614 -6144 -1296 2633 -941 0 -7
- 5.000e-01 -338 -38 184 210 -3604 85 -86
- 1.000e+00
- Version 3	! _**NEW BLOCK STARTS HERE**_
- //NPAR
- 3
- //Zin, longhit_mask
- 0 01
- //Layers
- 1235F
- ......

## Orthogonalization

- The parameters and the constraints often come out coupled.
- Can be tracked down to the “Bayesian character” of the parameter linearization procedure.
- Can remove by orthogonalizing
- Better resolution.
- Remove nonlinearity from cross-talk.
- Stability/convergence

## Effect of orthogonalization

- //NPAR
- 3
- //Zin, longhit_mask
- 0 00
- //Layers
- 1234F
- 3.750000e-04 3.875000e-04 3.750000e-04 3.750000e-04 2.727077e-03 4.408198e-05
- 14 14 14 14 12 7
- 1.172e-05 869 127  -517 -528 9414 **17** 226
- 1.000e-03 7288 3569 -970 -3705 2834 **15** 112
- 7.670e-04 -1413 -397 713 1124 -1374 **-10** -393
- //Kernel
- 5.000e-01 238 -3102 6644 -3882 403 3 -69
- 5.000e-01 4614 -6144 -1296 2633 -941 0 -7
- 5.000e-01 -338 -38 184 210 -3604 85 -86
- 1.000e+00
- Version 3	! File format version number
- //NPAR
- 3
- //Zin, longhit_mask
- 0 00
- //Layers
- 1234F
- 3.750000e-04 3.875000e-04 3.750000e-04 3.750000e-04 2.727077e-03 4.408198e-05
- 14 14 14 14 12 7
- 1.172e-05 -18 -15 -2 10 95** 236** 4
- 1.000e-03 6425 3823 -548 -3499 -2921** 151** -32
- 7.670e-04 -1095 -502 462 1120 646 **-58** -334
- //Kernel
- 5.000e-01 2252 -5402 5198 -2221 51 -1 -60
- 5.000e-01 -3863 3990 3890 -3895 1085 -1 -20
- 5.000e-01 -340 -46 197 196 -3489 82 -83
- 1.000e+00

## Things to understand (list from last time)

- Efficiency (wide vs. narrow patterns ?) Lots of progress (not from myself)
- Fixes ?
- Some small strange effects remaining
- Coupling between parameters and 2
- Solved by orthogonalization
- Timing/TF combinatoric: are ‘narrow roads’ narrow enough for 20kHz rate ?
- Anybody looking at this ?
- Give up barrel-crossers ? (mech. only ?)
- Let’s vote !
- Start looking towards 4/5
- Can accommodate all constants in `fcon’
- SVT-Offline parameters match well; still want to cross-check gcon/patt gen. simple model to full simulation for small biases.

## Plan for startup

- Start over with 0123x_wide (new format)
- Go to orthogonalized constants
- Find beam position - make new gcon and patterns (~ 1 day)
- Reduce residual beam tilt
- If beam offset  > 1mm, add nonlinearity corrections
- Add internal corrections to gain extra ~micron and narrow 2