infresnel — API Reference

infresnel.infresnel.calculate_paths(src_lat, src_lon, rec_lat, rec_lon, dem_file=None, full_output=False)

Calculate elevation profiles, direct paths, and shortest diffracted paths.

Paths are calculated for a given DEM (either a user-supplied dem_file or automatically downloaded 1 arc-second SRTM data) and an arbitrary number of source-receiver pairs. By default, the function returns only the path length differences. If full_output is set to True, then the complete path information (lengths, coordinates, etc.) and the DEM used are returned.

Note

Input coordinates are expected to be in the WGS 84 datum. DEM file vertical units are expected to be meters.

Parameters

  • src_lat (int or float) – Source latitude

  • src_lon (int or float) – Source longitude

  • rec_lat (int, float, list, tuple, or ndarray) – One or more receiver latitudes

  • rec_lon (int, float, list, tuple, or ndarray) – One or more receiver longitudes

  • dem_file (str or None) – Path to DEM file (if None, then SRTM data are used)

  • full_output (bool) – Toggle outputting full profile/path information and DEM, vs. just the path length differences

Returns

If full_output is False — an ndarray of path length differences [m], one per source-receiver pair

If full_output is True — a tuple of the form (ds_list, dem) where ds_list is a list of Dataset objects, one per source-receiver pair, containing full profile and path information, and dem is a DataArray containing the UTM-projected DEM used to compute the profiles

infresnel.infresnel.calculate_paths_grid(src_lat, src_lon, x_radius, y_radius, spacing, dem_file=None, output_file=None)

Calculate paths for a UTM-projected grid surrounding a source location.

Wrapper around calculate_paths() for computing path difference grids. See the docstring for that function for a description of how DEM data are handled.

Note

Input coordinates are expected to be in the WGS 84 datum. DEM file vertical units are expected to be meters.

Parameters

  • src_lat (int or float) – Source latitude

  • src_lon (int or float) – Source longitude

  • x_radius (int, float, list, or tuple) – [m] Desired grid radius in \(x\)-direction, measured from source location (specify a two-element array for different west and east extents)

  • y_radius (int, float, list, or tuple) – [m] Desired grid radius in \(y\)-direction, measured from source location (specify a two-element array for different south and north extents)

  • spacing (int or float) – [m] Desired grid spacing

  • dem_file (str or None) – Path to DEM file (if None, then SRTM data are used)

  • output_file (str or None) – If a string filepath is provided, then an RGB GeoTIFF file containing the colormapped grid of path length difference values is exported to this filepath (no export if None)

Returns

Tuple of the form (path_length_differences, dem) where path_length_differences is a DataArray grid of path length differences [m], and dem is a DataArray containing the UTM-projected DEM used to compute the profiles

Return type

tuple