Generation Functions

Generation functions create distributions of points or cells for spatial analysis.

Points

Fibonacci Lattice

tatc.generation.generate_fibonacci_lattice_points(distance: float, elevation: float = 0, mask: Optional[Union[Polygon, MultiPolygon]] = None) → GeoDataFrame[source]

Generates geodetic points following a Fibonacci lattice.

See: Gonzalez (2010). “Measurement of areas on a sphere using Fibonacci and latitude-longitude lattices”, Mathematical Geosciences 42(49). doi: 10.1007/s11004-009-9257-x

Note: this implementation differs slightly from Gonzalez. Gonzalez requires an odd number of points. This implementation allows any number of points. In agreement with Gonzalez, no points are placed at poles.

Parameters

  • distance (float) – The typical surface distance (meters) between points.

  • elevation (float) – The elevation (meters) above the datum in the WGS 84 coordinate system.

  • mask (Polygon or MultiPolygon) – An optional mask to constrain points using WGS84 (EPSG:4326) geodetic coordinates in a Polygon or MultiPolygon.

Returns

the data frame of generated points

Return type

geopandas.GeoDataFrame

Cubed Sphere

tatc.generation.generate_cubed_sphere_points(distance: float, elevation: float = 0, mask: Optional[Union[Polygon, MultiPolygon]] = None) → GeoDataFrame[source]

Generates geodetic points at the centroid of regular cubed-sphere grid cells.

See: Putman and Lin (2007). “Finite-volume transport on various cubed-sphere grids”, Journal of Computational Physics, 227(1). doi: 10.1016/j.jcp.2007.07.022

Parameters

  • distance (float) – The typical surface distance (meters) between points.

  • elevation (float) – The elevation (meters) above the datum in the WGS 84 coordinate system.

  • mask (Polygon or MultiPolygon) – An optional mask to constrain points using WGS84 (EPSG:4326) geodetic coordinates in a Polygon or MultiPolygon.

Returns

the data frame of generated points

Return type

geopandas.GeoDataFrame

Cells

Cubed Sphere

tatc.generation.generate_cubed_sphere_cells(distance: float, elevation: float = 0, mask: Optional[Union[Polygon, MultiPolygon]] = None, strips: Optional[str] = None) → GeoDataFrame[source]

Generates geodetic polygons over a regular cubed-sphere grid.

See: Putman and Lin (2007). “Finite-volume transport on various cubed-sphere grids”, Journal of Computational Physics, 227(1). doi: 10.1016/j.jcp.2007.07.022

Parameters

  • distance (float) – The typical surface distance (meters) between points.

  • elevation (float) – The elevation (meters) above the datum in the WGS 84 coordinate system.

  • mask (Polygon or MultiPolygon) – An optional mask to constrain cells using WGS84 (EPSG:4326) geodetic coordinates in a Polygon or MultiPolygon.

  • strips (str) – Option to generate strip-cells along latitude (“lat”), longitude (“lon”), or none (None).

Returns

the data frame of generated cells

Return type

geopandas.GeoDataFrame