bounds

Classes

BoundingBox

Module Contents

class bounds.BoundingBox(x_min, x_max, y_min, y_max, crs=coordinate_reference_systems.DEFAULT_CRS)
contains_point(point, crs=None)

Determine whether or not a point lies within this bounding box.

Parameters:

  • point (tuple) – An x, y tuple representing the coordinates of the point.

  • crs (cartopy.crs.CRS, optional) – The coordinate reference system on which the x and y coordinates of the given point are defined. If None (default), assumes the input point uses the same coordinate reference system as this bounding box.

Return type:

bool

crs
property east

Convenience property to access this bbox’s furthest east point.

classmethod from_bbox(bbox, source_crs=None, target_crs=None)

Generate a bounding box which completely contains another bounding box.

The intended use case of this method is to generate a bounding box on a different coordinate reference system to an input bounding box, ensuring that the entire input bounding box is countained.

Parameters:

  • bbox (list or earthkit.plots.geo.bounds.BoundingBox) – The bounding box around which to generate a new bounding box. If a list, mus

  • source_crs (cartopy.crs.CRS, optional) – The coordinate reference system of the source bounding box. If None (default), assumes a cylindrical lat-lon CRS, unless the source bounding box is an earthkit.plots.geo.bounds.BoundingBox with its own CRS.

  • target_crs (cartopy.crs.CRS, optional) – The coordinate reference system in which to generate a new bounding box which entriely contains the input bounding box. If None (default), attempts to find an “optimised” target CRS based on the domain extents.

Return type:

earthkit.plots.geo.bounds.BoundingBox

classmethod from_geometry(geometry, source_crs=coordinate_reference_systems.DEFAULT_CRS, target_crs=None)

Generate a tight bounding box around a geometry.

Parameters:

  • geometry (shapely.geometry) – A shapely geometry around which the bounding box should be drawn.

  • source_crs (cartopy.crs.CRS, optional) – The coordinate reference system on which the geometry’s coordinates are defined. If None, assumes a cylindrical lat-lon CRS.

  • target_crs (cartopy.crs.CRS, optional) – The target coordinate reference system for the generated bounding box.

Return type:

earthkit.plots.geo.bounds.BoundingBox

property north

Convenience property to access this bbox’s furthest north point.

property south

Convenience property to access this bbox’s furthest south point.

to_bbox(target_crs)

Convert bounding box onto a new coordinate reference system.

Paratemers

target_crscartopy.crs.CRS

The coordinate reference system to use for the new bounding box.

rtype:

earthkit.plots.geo.BoundingBox

to_cartopy_bounds()

Convert bounding box to a cartopy-compatible list of bounds.

Return type:

tuple

to_latlon_bbox()

Generate a tight bounding box around a geometry.

Parameters:

  • geometry (shapely.geometry) – A shapely geometry around which the bounding box should be drawn.

  • source_crs (cartopy.crs.CRS, optional) – The coordinate reference system on which the geometry’s coordinates are defined. If None, assumes a cylindrical lat-lon CRS.

  • target_crs (cartopy.crs.CRS, optional) – The target coordinate reference system for the generated bounding box.

Return type:

earthkit.plots.geo.bounds.BoundingBox

to_optimised_bbox()

Generate a new bounding box using the “optimised” CRS for these extents.

The method for choosing an optimised CRS is as follows:

  • If the area of the map is greater than 60% of the globe, use a global equirectangular CRS.

  • If the central latitude is within ±25 degrees, use an equirectangular CRS.

  • If the central latitude is greater (less) than +(-)75 degrees, use a North (South) Polar Stereo CRS.

  • If the central latitude falls between ±25 and ±75 degrees and the aspect ratio is > 0.8, use an Albers Equal Area CRS.

  • If the central latitude falls between ±25 and ±75 degrees and the aspect ratio is < 0.8, use a Transverse Mercator CRS.

This method is adapted from the method used by https://projectionwizard.org, which is discussed in the following article: Šavrič, B., Jenny, B. and Jenny, H. (2016). Projection Wizard – An online map projection selection tool. The Cartographic Journal, 53–2, p. 177–185. Doi: 10.1080/00087041.2015.1131938.

Parameters:

bounds (list) – The latitude and longitude extents of the bounding box, given as [min_longitude, max_longitude, min_latitude, max_latitude].

Return type:

cartopy.crs.CRS

property west

Convenience property to access this bbox’s furthest west point.

x_max
x_min
y_max
y_min