Fix and clarify parameter conversions.

Fix and (hopefully) clarify parameter conversions.

Signed-off-by: Peter Diener <diener@cct.lsu.edu>

1 files changed, 19 insertions, 9 deletions

diff --git a/doc/PARAMETERS b/doc/PARAMETERS
index 14e4369..67e594a 100644
--- a/doc/PARAMETERS
+++ b/doc/PARAMETERS
@@ -1,9 +1,13 @@
 Comparison between BSSN_MoL (ADM_BSSN) and McLachlan (ML_BSSN) parameters
 
-2009-11-14: Written by Erik Schnetter, not yet trustworthy
-XXXX-XX-XX: Cross-checked by NNN
+2009-11-14: Written by Erik Schnetter
+2010-03-29: Cross-checked by Peter Diener, fixed a few issues with the gauge
+            parameters and (hopefully) clarified things a bit.
 
+Activation:
 
+ActiveThorns = "BSSN_MoL"
+        ActiveThorns = "ML_BSSN ML_BSSN_Helper"
 
 Formulation:
 
@@ -40,9 +44,12 @@ ADMBase::lapse_evolution_method = "1+log"
         ML_BSSN::harmonicN = 1   # 1+log
 
 ADM_BSSN::lapsesource = "straight"
-        ML_BSSN::AlphaDriver = 0
+        ML_BSSN::LapseAdvectionCoeff = 1
+        [This can only be done with the shift advection terms on the lapse]
 ADM_BSSN::lapsesource = "modified"
         ML_BSSN::AlphaDriver = 1
+	ML_BSSN::LapseAdvectionCoeff = 0
+        [This can only be done with the shift advection terms turned off]
 
 ADM_BSSN::harmonic_f
         ML_BSSN::harmonicF
@@ -54,7 +61,9 @@ ADM_BSSN::force_lapse_minimum
 
 ADM_BSSN::lapse_advection_coeff
         ML_BSSN::LapseAdvectionCoeff
-        [should be 0 or 1]
+        [should be 0 or 1. Note that in McLachlan this also selects
+        between using the 1st time derivative lapse or not. Maybe this
+        should be changed.]
 
 
 
@@ -64,27 +73,28 @@ ADMBase::shift_evolution_method = "gamma0"
         ADMBase::shift_evolution_method   = "ML_BSSN"
         ADMBase::dtshift_evolution_method = "ML_BSSN"
         ML_BSSN::ShiftGammaCoeff = 0
+ADMBase::shift_evolution_method = "gamma1"
+        [Not implemnted in ML_BSSN]
 ADMBase::shift_evolution_method = "gamma2"
-        ADMBase::shift_evolution_method   = "ML_BSSN"
-        ADMBase::dtshift_evolution_method = "ML_BSSN"
-        ML_BSSN::ShiftGammaCoeff = 1
+        [Not implemnted in ML_BSSN]
 
 ADM_BSSN::ShiftGammaCoeff
         ML_BSSN::ShiftGammaCoeff
+        [Normally chosen to be 0.75 for moving puncture gauges]
 
 ADM_BSSN::ShiftAlpPower = 0
         [always for ML_BSSN]
         [There is a parameter ML_BSSN::ShiftAlphaPower, but it is unused]
 
 ADM_BSSN::GammaDriver
-        [has no effect in ADM_BSSN]
+        [has no effect in ADM_BSSN and is not implemented in ML_BSSN]
 
 ADM_BSSN::BetaDriver
         ML_BSSN::BetaDriver
 
 ADM_BSSN::gamma_driver_advection_coeff
         ML_BSSN::ShiftAdvectionCoeff
-        [should be 0 or 1]
+        [should be 0 or 1. For moving puncture gauges 1 should be chosen]
 
 ADM_BSSN::ApplyShiftBoundary = no
         [not possible with ML_BSSN; shift boundary is always applied]