Problem Config file

The config file is used to generate a simulation model that can be executed with the application pyparticle_app:

pyparticle_app ma_simul.cfg

The config files are based on the sintax rfc822 used by the python configparser module, very easy to read and edit and used in numerous applications.

Creating a simulation using the config file is quite easy, as first you must create a model file with the commands:

pyparticle_app -m
mv example_pyparticles_config.cfg my_sim.cfg

And after this you must edit the file according you criteria. Observe that the uneeded parameters are ignored; if there are an editing error normally is used the default value or the application exit with an exception.

Config file description:

Section: pset_origin

Define the origin of the particles data set.

Varibles

Variable	Description
media_origin = [file|rand]	Where data the is stored
file_name = <file>	the dataset file name

Section: set_config

Particles data set configauration

Varibles:

Variable	Description
len_unit = <number>	How many meters is a unit
mass_unit = <number>	How many Kg is a unit
boundary = [open|periodic|rebound]	The boundary model used in the simulation
boundary_lim = <#> <#>	Define the size of the boundary
sim_log = <number>	The size of the log queue (0 disable the log)
sim_log_X = [True|False]	If sim_log is enabled log the position
sim_log_V = [True|False]	If sim_log is enabled log the velocities
rand_part_nr = <number>	The total number of particles for a rand set

Note: len_unit & mass_unit are used only for drawing the particles

Section: model

Simulation method and force model

Varibles:

Variable	Description
force = [gravity|linear_spring|constant_force]	Force type used
ode_solver_name = [euler|runge_kutta|leap_frog|midpoint]	Integration method
time_step = <number>	time step used for the integration
force_const = <number>	Force constant, like G
force_vector= <number>	Force vector, for the constant force

Section: animation

Simulation control & graphic wiew

Variables:

Variable	Description
animation_type = [opengl|matplotlib]	Setup the output interface
draw_log = [True|False]	Draw the simulation log (if enabled)
xlim = <number> <number>	define the limit of the picture (sometime unused)
ylim = <number> <number>
zlim = <number> <number>

Examples:

The solar system:

[pset_origin]
media_origin = file
file_name = solar_sys.csv

[set_config]
len_unit = 149597870700.0
mass_unit = 5.9736e24
boundary = open

[model]
force = gravity
ode_solver_name = euler
time_step = 3600
steps = 1000000
force_const = 6.67384e-11
force_vector = 0 0 0

[animation]
animation_type = opengl
xlim = -5.0  5.0
ylim = -5.0  5.0
zlim = -5.0  5.0

Random cluster:

# this is a comment
[pset_origin]
media_origin = rand
# Ignored !!!
file_name = solar_sys.csv

[set_config]
len_unit = 1
mass_unit = 1
boundary = open
boundary_lim = -7 7
sim_log = 0
sim_log_x = True
sim_log_v = False
# Attention: the total number of particles is here !!
rand_part_nr = 350

[model]
force = gravity
ode_solver_name = runge_kutta
time_step = 0.005
steps = 1000000
force_const = 0.001
# ignored
force_vector = 0 0 -7

[animation]
animation_type = opengl
draw_trajectory = False
trajectory_step = 15
xlim = -5.0  5.0
ylim = -5.0  5.0
zlim = -5.0  5.0

# Randon cluster definition
[rand_cluster_bar]
rc_part_nr = 150
rc_centre = 0 0 1
rc_radius = 1.0
rc_mass_rng = 0.5  1.0
rc_vel_rng = 0.1 0.2
rc_vel_mdl = no
rc_vel_dir = 0 1 0

[rand_cluster_foo]
rc_part_nr = 150
rc_centre = 0 0 -1
rc_radius = 2.0
rc_mass_rng = 0.5  2.0
rc_vel_rng = 0.021 0.2
rc_vel_mdl = const
rc_vel_dir = 1 1 0

[rand_cluster_foobar]
rc_part_nr = 50
rc_centre = 0 3 -3
rc_radius = 2.0
rc_mass_rng = 0.2  2.0
rc_vel_rng = .1 .2
rc_vel_mdl = bomb
rc_vel_dir = 0 1 0