Extract per-trip descriptors from PDS tracks — describe_pds

One row per trip, carrying the geometry and signal-quality measures validate_pds_trips() builds its alerts on:

Usage

describe_pds_tracks(log_threshold = logger::DEBUG)

Arguments

log_threshold: The (standard Apache logj4) log level used as a threshold for the logging infrastructure. See logger::log_levels for more details

Value

no outputs. This function is used for it's side effects

Details

start_end_distance — metres between the first and last point of a trip, which is how a one-way trip is spotted (alert 12).
outliers_proportion — percentage of points faster than 30 m/s, and timetrace_dispersion — the standard deviation of the interval between consecutive points (together, alert 13).
start_lat / start_lng / end_lat / end_lng, which merge_consecutive_trips() needs to decide whether two trips of the same boat are really one.

The step is incremental: only trips absent from the previous descriptors artefact are read. Both workflow steps run, coasts' for the grids and this one for the descriptors.

The parameters needed are:

pds:
  pds_tracks:
    file_prefix:
    descriptors:
      file_prefix:
      version:
pds_storage:
  google:
    key:
    options:

Progress through the function is tracked using the package logger.