Observation Geometry¶

Calculate azimuth and elevation independently of TEC, using broadcast navigation loaded once with read_rinex_nav. The TEC Calculation guide shows the complete workflow.

compute_az_el ¶

compute_az_el(
    observations: DataFrame | LazyFrame,
    header: RinexObsHeader,
    navigation: NavigationData,
    *,
    overwrite: bool = False,
) -> pl.LazyFrame

[source]

Append satellite azimuth and elevation to observations from one station.

Parameters:

Name	Type	Description	Default
`observations`	`DataFrame or LazyFrame`	Wide or long observations with time, station and prn. Time must be timezone-aware UTC or timezone-naive GPS. Existing rx_lat/rx_lon columns override header coordinates in degrees; height follows the header's receiver history in metres.	required
`header`	`RinexObsHeader`	Observation time-scale and receiver-position metadata.	required
`navigation`	`NavigationData`	Broadcast ephemerides loaded by read_rinex_nav. Reuse this object across calls to avoid repeated decoding and indexing.	required
`overwrite`	`bool`	Replace both angle columns if either already exists. False raises rather than mixing existing and newly computed angles.	`False`

Returns:

Type	Description
`LazyFrame`	Original rows, columns and time values plus Float64 azimuth/elevation in degrees. Azimuth is clockwise from north in [0, 360); elevation is in [-90, 90]. Unavailable geometry is null; no elevation filter or TEC quality control is applied. Query collection and satellite propagation complete before return; angle evaluation remains lazy.

Raises:

Type	Description
`TypeError`	If navigation is not NavigationData or time is not Datetime.
`ValueError`	If required columns are absent, time/PRN is invalid, multiple stations are present, or existing angle columns would be overwritten.