Vex

class pride.io.Vex(file: str | pathlib.Path)

Interface to VEX files.

load_observation_modes() → dict[str, pride.types.ObservationMode]

Load observation modes from the VEX file

An observation mode is a configuration for the experiment, and it specifies the frequency band in which each of the antennas will operate. The VEX file can contain multiple observation modes.

This function reads information about the observation modes from the VEX into ObservationMode objects, and returns a dictionary in which each of these objects is indexed by the mode ID.

Returns:

Dictionary of observation modes

load_clock_parameters() → dict[str, tuple[datetime.datetime, float, float]]

Load clock offsets from $CLOCK section

[From VEX documentation] The $CLOCK section contains the necessary clock parameters for proper correlation of the data. Normally, this information will be taken from the station logs, transcribed manually or, as a last resort, determined from a fringe search at the correlator. [END] The returned dictionary has the ID of a station as key, and a tuple with the following items as value: - Epoch of origin for the clock model - Clock offset with respect to UTC [s] - Clock rate [s/s]

Return clock_parameters:

Dictionary with clock parameters for each station.

load_station_ids_and_names(ignored_stations: list[str] | None = None) → dict[str, str]

Load information from the $STATION section

Parses the STATION section of the VEX file to identify all the observatories potentially involved in the experiment. Checks the names of the antennas against a station catalog, normalizes them to ensure that they match the one used in the external data files of the delay and displacement models, and ensures that all of the IDs and names are unique.

Parameters:

ignored_stations – List with IDs of stations to ignore

Return stations:

Dictionary with the station IDs as keys, and their

normalized names as values.

load_source_data(source_name: str) → SourceData

Load information about a source

Loads the type information and, for calibrators, the observed coordinates from the VEX file. The function ensures that type information is present, that the source type is valid, and that the coordinates are specified in the J2000 reference frame. The information is loaded into a SourceData data structure.

Parameters:

source_name – Name of the source to load

Return source_data:

Data structure with information about the source

load_single_scan_data(scan_id: str, experiment_target: str) → ScanData

Return data about a single scan

Returns a ScanData object with the following information: - Source type - Source name: Uses experiment_target for source_type = “target” - Observation mode - Initial epoch for all stations - Initial and final time offsets for each station involved

Parameters:

• scan_id – ID of the scan to load

• experiment_target – Name of the target for the experiment

Return scan_data:

Data structure with information about the scan