SubarrayDescription

class ctapipe.instrument.SubarrayDescription(name, tel_positions=None, tel_descriptions=None, reference_location=None)

Bases: object

Collects the TelescopeDescription of all telescopes along with their positions on the ground.

Attributes

name: str

name of subarray

tel_coords: astropy.coordinates.SkyCoord

coordinates of all telescopes

tels:

dict of TelescopeDescription for each telescope in the subarray

Attributes Summary

COMPATIBLE_VERSIONS
CURRENT_TAB_VERSION
camera_types	Tuple of unique camera types in the array
footprint	area of smallest circle containing array on ground
n_tels	number of telescopes in this subarray
optics_types	Tuple of unique optics types in the array
tel	Dictionary mapping tel_ids to TelescopeDescriptions
tel_coords	returns telescope positions as astropy.coordinates.SkyCoord
tel_ids	telescope IDs as an array
tel_index_array	returns an expanded array that maps tel_id to tel_index.
tel_indices	returns dict mapping tel_id to tel_index, useful for unpacking lists based on tel_ids into fixed-length arrays
telescope_types	Tuple of unique telescope types in the array

Methods Summary

from_hdf(path[, focal_length_choice])
get_tel_ids(telescopes)	Convert a list of telescope ids and telescope descriptions to a list of unique telescope ids.
get_tel_ids_for_type(tel_type)	return tuple of tel_ids that have the given tel_type
get_tel_indices_for_type(tel_type)	return tuple of telescope indices that have the given tel_type
info([printer])	print descriptive info about subarray
multiplicity(tel_mask[, tel_type])	Compute multiplicity from a telescope mask
peek()	Draw a quick matplotlib plot of the array
read(path, **kwargs)	Read subarray from path
select_subarray(tel_ids[, name])	return a new SubarrayDescription that is a sub-array of this one
tel_ids_to_indices(tel_ids)	maps a telescope id (or array of them) to flat indices
tel_ids_to_mask(tel_ids)	Convert a list of telescope ids to a boolean mask of length n_tels where the index of the telescope is set to True for each tel_id in tel_ids
tel_mask_to_tel_ids(tel_mask)	Convert a boolean mask of selected telescopes to a list of tel_ids.
to_hdf(h5file[, overwrite, mode])	write the SubarrayDescription
to_table([kind])	export SubarrayDescription information as an astropy.table.Table

Attributes Documentation

COMPATIBLE_VERSIONS = {'2.0'}

CURRENT_TAB_VERSION = '2.0'

camera_types

Tuple of unique camera types in the array

The entries are ordered by camera name to be deterministic but the order should not be relied on.

footprint

area of smallest circle containing array on ground

n_tels

number of telescopes in this subarray

optics_types

Tuple of unique optics types in the array

The entries are ordered by optics name to be deterministic but the order should not be relied on.

tel

Dictionary mapping tel_ids to TelescopeDescriptions

tel_coords

returns telescope positions as astropy.coordinates.SkyCoord

tel_ids

telescope IDs as an array

tel_index_array

returns an expanded array that maps tel_id to tel_index. I.e. for a given telescope, this array maps the tel_id to a flat index starting at 0 for the first telescope. tel_index = tel_id_to_index_array[tel_id] If the tel_ids are not contiguous, gaps will be filled in by -1. For a more compact representation use the tel_indices

tel_indices

returns dict mapping tel_id to tel_index, useful for unpacking lists based on tel_ids into fixed-length arrays

telescope_types

Tuple of unique telescope types in the array

The entries are ordered by telescope name to be deterministic but the order should not be relied on.

Methods Documentation

classmethod from_hdf(path, focal_length_choice=<FocalLengthKind.EFFECTIVE: 1>)

get_tel_ids(telescopes: Iterable[Union[int, str, ctapipe.instrument.telescope.TelescopeDescription]]) → Tuple[int]

Convert a list of telescope ids and telescope descriptions to a list of unique telescope ids.

Parameters

telescopes: List[Union[int, str, TelescopeDescription]]

List of Telescope IDs and descriptions. Supported inputs for telescope descriptions are instances of TelescopeDescription as well as their string representation.

Returns

tel_ids: List[int]

List of unique telescope ids matching telescopes

get_tel_ids_for_type(tel_type) → Tuple[int]

return tuple of tel_ids that have the given tel_type

Parameters

tel_type: str or TelescopeDescription

telescope type string (e.g. ‘MST_MST_NectarCam’)

get_tel_indices_for_type(tel_type)

return tuple of telescope indices that have the given tel_type

Parameters

tel_type: str or TelescopeDescription

telescope type string (e.g. ‘MST_MST_NectarCam’)

info(printer=<built-in function print>)

print descriptive info about subarray

multiplicity(tel_mask, tel_type=None)

Compute multiplicity from a telescope mask

Parameters

tel_masknp.ndarray

Boolean array with last dimension of size n_telescopes

tel_typeNone, str or TelescopeDescription

If not given, compute multiplicity from all telescopes. If given, the multiplicity of the given telescope type will be computed.

Returns

multiplicityint or np.ndarray

Number of true values for given telescope mask and telescope type

peek()

Draw a quick matplotlib plot of the array

static read(path, **kwargs)

Read subarray from path

This uses the EventSource mechanism, so it should be able to read a subarray from any file supported by ctapipe or an installed io plugin.

kwargs are passed to the event source

select_subarray(tel_ids, name=None)

return a new SubarrayDescription that is a sub-array of this one

Parameters

tel_ids: list(int)

list of telescope IDs to include in the new subarray

name: str

name of new sub-selection

Returns

——-

SubarrayDescription

tel_ids_to_indices(tel_ids)

maps a telescope id (or array of them) to flat indices

Parameters

tel_idsint or List[int]

array of tel IDs

Returns

np.array:

array of corresponding tel indices

tel_ids_to_mask(tel_ids)

Convert a list of telescope ids to a boolean mask of length n_tels where the index of the telescope is set to True for each tel_id in tel_ids

Parameters

tel_idsint or List[int]

array of tel IDs

Returns

np.array[dtype=bool]:

Boolean array of length n_tels with indices of the telescopes in tel_ids set to True.

tel_mask_to_tel_ids(tel_mask)

Convert a boolean mask of selected telescopes to a list of tel_ids.

Parameters

tel_mask: array-like

Boolean array of length n_tels with indices of the telescopes in tel_ids set to True.

Returns

——-

np.array:

Array of selected tel_ids

to_hdf(h5file, overwrite=False, mode='a')

write the SubarrayDescription

Parameters

h5filestr, bytes, path or tables.File

Path or already opened tables.File with write permission

overwriteFalse

If the output path already contains a subarray, by default an error will be raised. Set overwrite=True to overwrite an existing subarray. This does not affect other content of the file. Use mode="w" to completely overwrite the output path.

modestr

If h5file is not an already opened file, the output file will be opened with the given mode. Must be a mode that enables writing.

to_table(kind='subarray')

export SubarrayDescription information as an astropy.table.Table

Parameters

kind: str

which table to generate (subarray or optics)