Configuration¶

Use TECConfig to select signals, geometry settings, quality thresholds, calibration and diagnostic output. Pass the configuration to any TEC calculation function, or omit it to create a fresh configuration with the default settings. Parameters are supplied by keyword, and configuration objects are frozen. Supplied code mappings are copied, although their nested contents remain mutable. See the configuration API for all defaults, field descriptions and validation rules.

Geometry and observation quality¶

Set the constellations, mapping model and quality thresholds when creating a configuration:

import gnss_tec as gt

config = gt.TECConfig(
    constellations="CG",
    ipp_height=400.0,
    min_elevation=30.0,
    min_snr=30.0,
    mapping_function="slm",
)

TEC calculation supports C (BeiDou) and G (GPS), and accepts either uppercase or lowercase letters. The default code preferences for RINEX 2 include GPS pairs only. Specify min_elevation in degrees and min_snr in dB-Hz. The SLM shell height is expressed in kilometers; MSLM uses a fixed height and angular factor. See scientific conventions for the mapping assumptions and how missing SNR values are handled.

Signal preferences¶

Use c1_codes and c2_codes to specify observation code preferences for each RINEX major version and constellation. The calculation selects the first complete code and phase pair that meets the QC and bias-coverage requirements. The two selections must use supported, distinct frequency bands.

For example, set the preferred GPS codes for RINEX 3:

config = gt.TECConfig(
    constellations="G",
    c1_codes={"3": {"G": ["C1C", "C1W"]}},
    c2_codes={"3": {"G": ["C2W", "C2C"]}},
)

You only need to supply the versions and constellations you want to change; unspecified entries retain their defaults. A supplied code list replaces the default list for that constellation. These preferences select among supported signals and do not add new constellation or signal-mode support. See TECConfig for the complete defaults.

Calibration¶

Use rx_bias to choose how receiver code bias is handled after satellite correction with a supplied bias product:

If no bias product is supplied, this option has no effect and the result remains uncorrected. If receiver bias estimation fails, the output records a failure status and leaves public TEC values null instead of applying a zero correction.

Use missing_bias to choose what happens when a supplied product lacks a required satellite or receiver match:

Check calibration status to determine which corrections were applied. A non-null TEC value can still be uncorrected or partially corrected.

Continuity mode¶

Use cycle_slip_mode to choose how phase discontinuities are handled:

All modes preserve the raw observations. The repair mode uses ordinary rates from neighboring past and future intervals, so it processes observations as an offline batch. It aligns every localized edge; code observations, noise estimates and integer constraints do not reject a correction. The correction does not recover per-carrier integers or identify the physical cause of an event. See quality and continuity for the method and its limits when studying ionospheric structure.

Diagnostic retention¶

Use retain_diagnostics to include the diagnostic columns needed for your analysis:

config = gt.TECConfig(retain_diagnostics=["mw", "qc_reason", "calibration_status"])

The default output omits epoch_flag, L1_lli, L2_lli, qc_valid, qc_reason and calibration_status; include them by name or select "all". You can also select mw, which is expressed in wide-lane cycles. Bias diagnostics are available when bias inputs are supplied. Geometry is always included, and selecting output columns does not change the calculation.

The internal columns tx_bias_start, tx_bias_end, rx_bias_start, rx_bias_end, level_id, offset and weight are excluded in every mode. Selecting an unsupported diagnostic name raises ValueError. The former retain_intermediate constructor argument is no longer accepted. See DIAGNOSTIC_COLUMNS for all supported diagnostic names.