4.1. xxx
|gravity> kali mkplummer.rb -n 3 -s 1 | kali nbody_set_id.rb > tmp.in
==> Plummer's Model Builder <==
Number of particles : N = 3
pseudorandom number seed given : 1
Floating point precision : precision = 16
Incremental indentation : add_indent = 2
Screen Output Verbosity Level : verbosity = 1
ACS Output Verbosity Level : acs_verbosity = 1
Floating point precision : precision = 16
Incremental indentation : add_indent = 2
actual seed used : 1
==> Takes an N-body system, and numbers all particles <==
The value of @body_id for the first particle: n = 1
Floating point precision : precision = 16
Screen Output Verbosity Level : verbosity = 1
ACS Output Verbosity Level : acs_verbosity = 1
Floating point precision : precision = 16
Incremental indentation : add_indent = 2
|gravity> kali world3.rb -t 0.1 -d 0.1 -o 0.1 < tmp.in > tmp.h
==> Individual Time Step, Individual Integration Scheme Code <==
Choice of integration method : integration_method = hermite
Determines the time step size : dt_param = 0.01
Initial timescale factor : init_timescale_factor = 0.01
Duration of an era : dt_era = 0.0078125
Maximum time step (units dt_era): dt_max_param = 1.0
Diagnostics output interval : dt_dia = 0.1
Snapshot output interval : dt_out = 0.1
Prune Factor : prune_factor = 0
Duration of the integration : t = 0.1
Max cputime diagnost. interval : cpu_time_max = 60
Screen Output Verbosity Level : verbosity = 1
ACS Output Verbosity Level : acs_verbosity = 1
Floating point precision : precision = 16
Incremental indentation : add_indent = 2
t = 0 (after 0, 0, 0 steps <,=,> t)
E_kin = 0.25 , E_pot = -0.5 , E_tot = -0.25
E_tot - E_init = 0
(E_tot - E_init) / E_init = -0
t = 0.1 (after 101, 0, 3 steps <,=,> t)
E_kin = 0.303 , E_pot = -0.553 , E_tot = -0.25
E_tot - E_init = -1.43e-10
(E_tot - E_init) / E_init = 5.72e-10
|gravity> kali world3.rb -t 0.1 -d 0.1 -g leapfrog -c 0.0001 -o 0.1 < tmp.in > tmp.l
==> Individual Time Step, Individual Integration Scheme Code <==
Choice of integration method : integration_method = leapfrog
Determines the time step size : dt_param = 0.0001
Initial timescale factor : init_timescale_factor = 0.01
Duration of an era : dt_era = 0.0078125
Maximum time step (units dt_era): dt_max_param = 1.0
Diagnostics output interval : dt_dia = 0.1
Snapshot output interval : dt_out = 0.1
Prune Factor : prune_factor = 0
Duration of the integration : t = 0.1
Max cputime diagnost. interval : cpu_time_max = 60
Screen Output Verbosity Level : verbosity = 1
ACS Output Verbosity Level : acs_verbosity = 1
Floating point precision : precision = 16
Incremental indentation : add_indent = 2
t = 0 (after 0, 0, 0 steps <,=,> t)
E_kin = 0.25 , E_pot = -0.5 , E_tot = -0.25
E_tot - E_init = 0
(E_tot - E_init) / E_init = -0
t = 0.1 (after 8503, 0, 3 steps <,=,> t)
E_kin = 0.303 , E_pot = -0.553 , E_tot = -0.25
E_tot - E_init = 2.04e-10
(E_tot - E_init) / E_init = -8.18e-10
|gravity> kali world3.rb -t 0.1 -d 0.1 -g multistep -o 0.1 < tmp.in > tmp.m
==> Individual Time Step, Individual Integration Scheme Code <==
Choice of integration method : integration_method = multistep
Determines the time step size : dt_param = 0.01
Initial timescale factor : init_timescale_factor = 0.01
Duration of an era : dt_era = 0.0078125
Maximum time step (units dt_era): dt_max_param = 1.0
Diagnostics output interval : dt_dia = 0.1
Snapshot output interval : dt_out = 0.1
Prune Factor : prune_factor = 0
Duration of the integration : t = 0.1
Max cputime diagnost. interval : cpu_time_max = 60
Screen Output Verbosity Level : verbosity = 1
ACS Output Verbosity Level : acs_verbosity = 1
Floating point precision : precision = 16
Incremental indentation : add_indent = 2
t = 0 (after 0, 0, 0 steps <,=,> t)
E_kin = 0.25 , E_pot = -0.5 , E_tot = -0.25
E_tot - E_init = 0
(E_tot - E_init) / E_init = -0
t = 0.1 (after 101, 0, 3 steps <,=,> t)
E_kin = 0.303 , E_pot = -0.553 , E_tot = -0.25
E_tot - E_init = 5.85e-10
(E_tot - E_init) / E_init = -2.34e-09
|gravity> kali world3.rb -t 0.1 -d 0.1 -g rk4 -o 0.1 < tmp.in > tmp.r
==> Individual Time Step, Individual Integration Scheme Code <==
Choice of integration method : integration_method = rk4
Determines the time step size : dt_param = 0.01
Initial timescale factor : init_timescale_factor = 0.01
Duration of an era : dt_era = 0.0078125
Maximum time step (units dt_era): dt_max_param = 1.0
Diagnostics output interval : dt_dia = 0.1
Snapshot output interval : dt_out = 0.1
Prune Factor : prune_factor = 0
Duration of the integration : t = 0.1
Max cputime diagnost. interval : cpu_time_max = 60
Screen Output Verbosity Level : verbosity = 1
ACS Output Verbosity Level : acs_verbosity = 1
Floating point precision : precision = 16
Incremental indentation : add_indent = 2
t = 0 (after 0, 0, 0 steps <,=,> t)
E_kin = 0.25 , E_pot = -0.5 , E_tot = -0.25
E_tot - E_init = 0
(E_tot - E_init) / E_init = -0
t = 0.1 (after 101, 0, 3 steps <,=,> t)
E_kin = 0.303 , E_pot = -0.553 , E_tot = -0.25
E_tot - E_init = -1.97e-11
(E_tot - E_init) / E_init = 7.86e-11
|gravity> cat tmp.h tmp.l | kali nbody_diff.rb
==> 6N-dimensional phase space distance between two N-body systems <==
Floating point precision : precision = 2
Screen Output Verbosity Level : verbosity = 1
ACS Output Verbosity Level : acs_verbosity = 1
Floating point precision : precision = 16
Incremental indentation : add_indent = 2
6N-dim. phase space dist. for two 3-body systems: 1.6577260953383540e-09
|gravity> cat tmp.h tmp.m | kali nbody_diff.rb
==> 6N-dimensional phase space distance between two N-body systems <==
Floating point precision : precision = 2
Screen Output Verbosity Level : verbosity = 1
ACS Output Verbosity Level : acs_verbosity = 1
Floating point precision : precision = 16
Incremental indentation : add_indent = 2
6N-dim. phase space dist. for two 3-body systems: 6.0710519740368357e-09
|gravity> cat tmp.h tmp.r | kali nbody_diff.rb
==> 6N-dimensional phase space distance between two N-body systems <==
Floating point precision : precision = 2
Screen Output Verbosity Level : verbosity = 1
ACS Output Verbosity Level : acs_verbosity = 1
Floating point precision : precision = 16
Incremental indentation : add_indent = 2
6N-dim. phase space dist. for two 3-body systems: 7.7645385253603229e-10