Cube coordinate functionality

aeolus.coord.add_binned_coord(cube, coord_name, bins)[source]

Bin coordinate points and add them as an auxiliary coordinate to a cube.

Parameters
Returns

Return type

iris.cube.Cube

aeolus.coord.add_cyclic_point_to_cube(cube, coord='longitude')[source]

Add a cyclic point to a cube and a corresponding coordinate.

A wrapper for cartopy.util.add_cyclic_point(), generalising it for iris cubes.

Parameters

  • cube (iris.cube.Cube) – An n-dimensional cube of data to add a cyclic point to.

  • coord (iris.coords.Coord or str) – A 1-dimensional coordinate which specifies the coordinate values for the dimension the cyclic point is to be added to. The coordinate values must be regularly spaced. Defaults to the “x”-coordinate.

Returns

The cube with a cyclic point added.

Return type

cyclic_cube

aeolus.coord.add_planet_calendar(cube, time_coord, days_in_year, days_in_month, days_in_day, run_start_day=0, seasons='djf', 'mam', 'jja', 'son', planet='planet')[source]

Add an auxiliary time axis with the non-Earth period lengths.

Parameters

  • cube (iris.cube.Cube) – Input cube.

  • time_coord (iris.coords.Coord or str) – Original time coordinate of the cube.

  • days_in_year (int or float) – Number of Earth days in one year on the given planet.

  • days_in_month (int or float) – Number of Earth days in one month on the given planet.

  • days_in_day (int or float) – Number of Earth days in one day on the given planet (e.g. ~16 for Titan).

  • run_start_day (int or float, optional) – Earth day of the start of the simulation.

  • seasons (tuple, optional) – Sequences of letters corresponding to month names.

  • planet (str, optional) – Name of the planet to be used to name the new coordinate.

aeolus.coord.area_weights_cube(cube, r_planet=None, normalize=False, model=<class 'aeolus.model.base.Model'>(53 fields))[source]

Create a cube of area weights for an arbitrary planet.

Parameters

  • cube (iris.cube.Cube) – Cube with longitude and latitude coordinates

  • r_planet (float, optional) – Radius of the planet (m). If not given, an attempt is made to get it from the cube metadata.

  • normalize (bool, optional) – Normalize areas.

  • model (aeolus.model.Model, optional) – Model class with relevant coordinate names.

Returns

Cube of area weights with the same metadata as the input cube

Return type

iris.cube.Cube

aeolus.coord.coarsen_cube(cube, lon_bins, lat_bins, model=<class 'aeolus.model.base.Model'>(53 fields))[source]

Block-average cube in longitude and latitude.

Note: no weighting is applied!

Parameters

  • cube (iris.cube.Cube) – Cube with longitude and latitude coordinates.

  • lon_bins (array-like) – Longitude bins.

  • lat_bins (array-like) – Latitude bins.

  • model (aeolus.model.Model, optional) – Model class with relevant coordinate names.

Returns

Return type

iris.cube.Cube

aeolus.coord.coord_to_cube(cube, coord)[source]

Convert coordinate points to a cube of the same dimension as the given cube.

Parameters
Returns

Cube of broadcast coordinate.

Return type

iris.cube.Cube

aeolus.coord.coord_delta_to_cube(cube, coord, normalize=False)[source]

Convert 1D coordinate spacings to a cube of the same dimension as the given cube.

Parameters

  • cube (iris.cube.Cube) – Cube containing the coordinate to be broadcast.

  • coord (str or iris.coords.Coord) – Coordinate to be broadcast.

  • normalize (bool, optional) – Normalize the data.

Returns

Cube of broadcast coordinate deltas.

Return type

iris.cube.Cube

aeolus.coord.ensure_bounds(cube, coords=('x', 'y'), model=<class 'aeolus.model.base.Model'>(53 fields))[source]

Auto-generate bounds for cube coordinates.

aeolus.coord.get_cube_datetimes(cube, model=<class 'aeolus.model.base.Model'>(53 fields))[source]

Convert points of a cube’s time coordinate to datetimes.

Parameters

  • cube (iris.cube.Cube) – Cube containing a time coordinate.

  • model (aeolus.model.Model, optional) – Model class with relevant coordinate names.

Returns

Array of datetime-like objects.

Return type

numpy.array

aeolus.coord.get_cube_rel_days(cube, model=<class 'aeolus.model.base.Model'>(53 fields))[source]

Convert points of a cube’s time coordinate to relative number of days.

Parameters

  • cube (iris.cube.Cube) – Cube containing a time coordinate.

  • model (aeolus.model.Model, optional) – Model class with relevant coordinate names.

Returns

Array of relative days.

Return type

numpy.array

aeolus.coord.get_dim_coord(cube, axis)[source]

Return a coordinate from a cube based on the axis it represents.

Uses iris.util.guess_coord_axis() to heuristically match a dimensional coordinate with the requested axis.

Adapted from https://github.com/LSaffin/iris-extensions

Parameters

  • cube (iris.cube.Cube) – Cube with the desired coordinate.

  • axis (str) – The co-ordinate axis to take from the cube. Must be one of X, Y, Z, T.

Returns

The dimensional coordinate matching the requested axis on the given cube.

Return type

iris.coords.DimCoord

Raises

  • ArgumentError – If axis is not one of {X, Y, Z, T}.:

  • NotFoundError – If the cube does not contain a coord with the requested axis.:

aeolus.coord.isel(obj, coord, idx, skip_not_found=None)[source]

Slice cubes by an index of a coordinate (index-selector).

Parameters

  • obj (iris.cube.Cube or iris.cube.CubeList) – Cube or list of cubes.

  • coord (str or iris.coords.Coord) – Coordinate for selection.

  • idx (int) – Index along the given coordinate.

  • skip_not_found (bool or str, optional) – Skip if coordinate not found. By default it is active when dealing with a cube list and inactive if dealing with a single cube.

Returns

Slice along the coordinate.

Return type

iris.cube.Cube or iris.cube.CubeList

aeolus.coord.nearest_coord_value(cube, coord_name, val)[source]

Get the nearest value of a coordinate.

Parameters
Returns

Element of the coordinate array closest to the given val.

Return type

int or float

aeolus.coord.not_equal_coord_axes(cube1, cube2)[source]

Given 2 cubes, return axes of unequal dimensional coordinates.

aeolus.coord.regrid_3d(cube, target, model=<class 'aeolus.model.base.Model'>(53 fields))[source]

Regrid a cube in the horizontal and in the vertical on to coordinates of the target cube.

Adapted from https://github.com/LSaffin/iris-extensions

Parameters

  • cube (iris.cube.Cube) – The cube to be regridded.

  • target (iris.cube.Cube) – The cube to regrid to.

  • model (aeolus.model.Model, optional) – Model class with relevant coordinate names.

Returns

Return type

iris.cube.Cube

aeolus.coord.replace_z_coord(cube, model=<class 'aeolus.model.base.Model'>(53 fields))[source]

Replace dimensional vertical coordinate.

Parameters

  • cube (iris.cube.Cube) – Input cube.

  • model (aeolus.model.Model, optional) – Model class with relevant coordinate names.

Returns

Copy of the input cube with a new vertical coordinate.

Return type

iris.cube.Cube

aeolus.coord.roll_cube_0_360(cube_in, model=<class 'aeolus.model.base.Model'>(53 fields))[source]

Take a cube spanning -180…180 degrees in longitude and roll it to 0…360 degrees.

Works with global model output, and in some cases for regional.

Parameters

  • cube (iris.cube.Cube) – Cube with longitude and latitude coordinates.

  • model (aeolus.model.Model, optional) – Model class with a relevant longitude coordinate name.

Returns

Return type

iris.cube.Cube

See also

aeolus.coord.roll_cube_pm180()

aeolus.coord.roll_cube_pm180(cube_in, model=<class 'aeolus.model.base.Model'>(53 fields))[source]

Take a cube spanning 0…360 degrees in longitude and roll it to -180…180 degrees.

Works with global model output, and in some cases for regional.

Parameters

  • cube (iris.cube.Cube) – Cube with longitude and latitude coordinates.

  • model (aeolus.model.Model, optional) – Model class with a relevant longitude coordinate name.

Returns

Return type

iris.cube.Cube

See also

aeolus.coord.roll_cube_0_360()

aeolus.coord.vertical_cross_section_area(cube2d, r_planet=None)[source]

Create a cube of vertical cross-section areas in metres.

aeolus.coord.volume_weights_cube(cube, r_planet=None, normalize=False, model=<class 'aeolus.model.base.Model'>(53 fields))[source]

Create a cube of volume weights from a grid of a given cube.

Parameters

  • cube (iris.cube.Cube) – Cube with longitude, latitude and height coordinates

  • r_planet (float, optional) – Radius of the planet (m). If not given, an attempt is made to get it from the cube metadata.

  • normalize (bool, optional) – Normalize the data.

  • model (aeolus.model.Model, optional) – Model class with relevant coordinate names.

Returns

Cube of area weights with the same metadata as the input cube

Return type

iris.cube.Cube