Meeting 2015 08 21¶
Generic settings¶
/N02/det/trackMaxSteps 1000000000
/N02/det/trackMaxLen 10 km
/gun/energy 10.9181415106 MeV
/N02/prec/setDeltaOne 1.0e-2 mm
/N02/prec/setDeltaInt 1.0e-5 mm
/N02/prec/setEpsilonMin 1.0e-3
/N02/prec/setEpsilonMax 1.0e-3
/N02/prec/setDeltaChord 0.25 mm
Experiment 1¶
/N02/det/stepMax 20. mm (i.e., stepMax = 20mm)
epsilonMax = epsilonMin = epsilon
The mean square error doesn't seem to vary.
The error, however, keeps growing with distance.
Why?
Error (y) vs. Distance (x) (only illustrative):
| epsilon | Simulation Time | Integration Steps | Mean Square Error |
|---|---|---|---|
| 1.0e-3 | 0m13.725s | 16500010 | 294 |
| 1.0e-4 | 0m13.725s | 16500010 | 294 |
| 1.0e-5 | 0m13.725s | 16500010 | 294 |
| 1.0e-6 | 0m21.815s | 38500010 | 294 |
| 1.0e-7 | 0m27.980s | 60500010 | 294 |
| 1.0e-8 | 0m41.054s | 104499999 | 294 |
| 1.0e-9 | 0m55.830s | 159500010 | 294 |
| 1.0e-10 | 1m25.948s | 269499999 | 294 |
| 1.0e-11 | 2m17.996s | 456500010 | 294 |
| 1.0e-12 | 3m50.224s | 786518324 | 294 |
Experiment 2¶
/N02/prec/setEpsilonMin 1.0e-3 (i.e, epsilon = 1.0e-3)
/N02/prec/setEpsilonMax 1.0e-3
Mean Square Error measured for first 15000 points (final time differs a lot, maybe we should consider some other measurment)
| stepMax [mm] | Simulation Time | Integration Steps | Mean Square Error |
|---|---|---|---|
| 0.2 | 13m34.816s | 550000011 | 0.00002 |
| 1 | 2m51.026s | 110000000 | 0.0006 |
| 2 | 1m28.192s | 55000000 | 0.002 |
| 5 | 0m33.121s | 22000000 | 0.017 |
| 10 | 0m21.907s | 22000010 | 0.068 |
| 20 | 0m13.797s | 16500010 | 0.27 |
| 50 | 0m8.319s | 13200010 | 1.65 |
| 100 | 0m7.179s | 13200020 | 6.34 |
| 150 | 0m6.848s | 13200020 | 13.68 |
| 200 | 0m6.382s | 12650020 | 23.31 |