Simulation¶

class plonk.Simulation¶

Smoothed particle hydrodynamics simulation object.

This class aggregates snapshot files, global quantity and sink time series data. Snapshot files contain a complete snapshot of the simulation at a particular time. Other files contain time series of global quantities on particles such as energy and momentum, and time series data for sink particles.

Examples

Reading simulation data into a Simulation object.

>>> sim = plonk.load_simulation('prefix', path_to_directory)

Accessing the snapshots.

>>> sim.snaps

Accessing the properties.

>>> sim.properties

Accessing the global quantity and sink time series data.

>>> sim.time_series['global']
>>> sim.time_series['sinks']

property code_units: Dict[str, Any]¶: Units associated with the simulation.

load_simulation(prefix, directory=None, data_source='Phantom')¶

Load Simulation.

Parameters

prefix (str) – Simulation prefix, e.g. ‘disc’, if files are named like disc_00000.h5, disc01.ev, discSink0001N01.ev, etc.
directory (optional) – Directory containing simulation snapshot files and auxiliary files. Default is None.
data_source (optional) – The SPH code used to produce the simulation data. Default is ‘Phantom’.

Return type

plonk.simulation.simulation.Simulation

property properties: Dict[str, Any]¶: Properties associated with the simulation.

set_units_on_time_series(config=None)¶

Set physical units on time series data.

Parameters: config (optional) – The path to a Plonk config.toml file.

property snaps: List[Snap]¶: List of Snap objects associated with the simulation.

property time_series: pandas.core.frame.DataFrame¶: Time series data.

to_array(quantity, indices=None)¶

Generate an array of a quantity over all snapshots.

Warning: this can be very memory intensive and slow.

Parameters

quantity (str) – The quantity as a string, e.g. ‘position’.
indices (Optional[List[int]]) – You can select a subset of particles by indices corresponding to snap[‘id’].

Returns

Return type

An array with units.

Examples

Get the position of every particle during the whole simulation.

>>> pos = sim.to_array(quantity='position')
>>> pos.shape
    (31, 1100000, 3)

unset_units_on_time_series(config=None)¶

Un-set physical units on time series data.

Parameters: config (optional) – The path to a Plonk config.toml file.

visualize(kind, **kwargs)¶

Visualize a simulation.

Parameters

sim (Simulation) – The Simulation object.
kind (str) – The kind of plot: ‘particle’, ‘image’, ‘vector’.
**kwargs – Keyword arguments to pass to plotting methods such as plonk.image, plonk.plot, and plonk.vector.

Returns

Return type

VisualizeSimulation

Examples

Visualize a simulation by density projection images.

>>> viz = visualize_sim(sim=sim, kind='image', quantity='density')

Alternatively.

>>> sim.visualize(kind='image', quantity='density')

Go forwards and backwards through snaps.

>>> viz.next()
>>> viz.prev()

Go to a particular snap, or skip ahead.

>>> viz.goto(10)
>>> viz.next(5)

plonk.load_simulation(prefix, directory=None, data_source='Phantom')¶

Load Simulation.

Parameters

prefix (str) – Simulation prefix, e.g. ‘disc’, if files are named like disc_00000.h5, disc01.ev, discSink0001N01.ev, etc.
directory (optional) – Directory containing simulation snapshot files and auxiliary files. Default is None.
data_source (optional) – The SPH code used to produce the simulation data. Default is ‘Phantom’.

Return type

plonk.simulation.simulation.Simulation

plonk.load_time_series(filenames, data_source='Phantom', config=None)¶

Load time series data from file(s).

Time series files track global quantities, such as energy, momentum, and density, over time. The time increments in these files is smaller than the snapshot file output time. These files are typically stored as text files.

The data is stored as a pandas DataFrame.

Parameters

filename(s) – Collection of paths to time series file(s) in chronological order. These should all contain the same columns.
data_source (optional) – The code used to produce the data. Default is ‘Phantom’.
config (optional) – The path to a Plonk config.toml file.
filenames (Union[str, pathlib.Path, Tuple[str], Tuple[pathlib.Path], List[str], List[pathlib.Path]]) –

Returns

A pandas DataFrame with the time series data.

Return type

dataframe

Examples

Reading a single time series file into a pandas DataFrame.

>>> file_name = 'simulation.ev'
>>> ts = plonk.load_time_series(file_name)

Reading a collection of time series files into a pandas DataFrame.

>>> file_names = ('sim01.ev', 'sim02.ev', 'sim03.ev')
>>> ts = plonk.load_time_series(file_names)

Snap

Analysis