Cube coordinate functionality

Functionality related to coordinates of cubes.

class aeolus.coord.CoordContainer(cubes, coord_check=False, model=Model [99 fields])[source]

Bases: object

Coordinate container.

{x,y,z,t}

Coordinates in the respective dimensions

Type:: iris.coord.Coord

__init__(cubes, coord_check=False, model=Model [99 fields])[source]

Instantiate an AtmosFlow object.

Parameters:

cubes (iris.cube.CubeList) – Atmospheric fields with necessary coordinates.
coord_check (bool, optional) – Check if all cubes have the same set of coordinates.
model (aeolus.model.Model, optional) – Model class with relevant coordinate and variable names.

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

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

Parameters:

cube (iris.cube.Cube) – Cube with the given coordinate.
coord_name (str or iris.coords.Coord) – Coordinate name.
bins (array-like) – Coordinate bins.

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() 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:

iris.cube.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.
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=Model [99 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.check_coords(cubes)[source]: Check the cubes coordinates for consistency.

aeolus.coord.coarsen_cube(cube, lon_bins, lat_bins, model=Model [99 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.

Return type:

iris.cube.Cube

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

Convert 1D coord spacings to a cube of the same dim 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.coord_to_cube(cube, coord, broadcast=True)[source]

Convert coordinate points to a cube with the same dimensions.

Parameters:

cube (iris.cube.Cube) – Cube containing the coordinate to be broadcast.
coord (str or iris.coords.Coord) – Coordinate to be broadcast.
broadcast (bool, optional) – Broadcast the coordinate points to the shape of the cube.

Returns:

Cube of broadcast coordinate.

Return type:

iris.cube.Cube

aeolus.coord.ensure_bounds(cube, coords=('x', 'y'), model=Model [99 fields])[source]: Auto-generate bounds for cube coordinates.

aeolus.coord.get_cube_datetimes(cube, model=Model [99 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.ndarray

aeolus.coord.get_cube_rel_days(cube, model=Model [99 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.ndarray

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 dim 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 given axis.:

aeolus.coord.get_xy_coords(cube, model=Model [99 fields])[source]

Return X and Y coords tuple using names from a given model container.

Parameters:

cube (iris.cube.Cube) – Input cube.
model (aeolus.model.Model, optional) – Model class with relevant coordinate and variable names.

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.interp_cube_from_height_to_pressure_levels(variable, pressure, levels, p_ref_frac=False, const=None, interpolator=None, model=Model [99 fields])[source]

Interpolate a cube from height to pressure level(s).

Parameters:

variable (iris.cube.Cube) – A cube to interpolate. Must have the same dimensions as the pressure cube.
pressure (iris.cube.Cube) – A cube of pressure.
levels (array-like) – Sequence of pressure levels (same units as the units of pressure cube in cubelist).
p_ref_frac (bool, optional) – If True, levels are used as fractions of the surface pressure.
const (aeolus.const.const.ConstContainer, optional) – Required if p_ref_frac=True. If not given, constants are attempted to be retrieved from attributes of a cube in the cube list.
interpolator (callable or None) – The interpolator to use when computing the interpolation. See relevel() docs for more.
model (aeolus.model.Model, optional) – Model class with relevant variable names.

Returns:

The variable interpolated to pressure level(s).

Return type:

iris.cube.Cube

aeolus.coord.interp_cubelist_from_height_to_pressure_levels(cubelist, levels, p_ref_frac=False, const=None, interpolator=None, model=Model [99 fields], include_pressure=False)[source]

Interpolate all cubes to the given set of pressure levels.

Pressure variable is found using the model.pres name and then optionally excluded from the output list of interpolated cubes.

Parameters:

cubelist (iris.cube.CubeList) – List of cubes, including a cube of pressure.
levels (array-like) – Sequence of pressure levels (same units as the units of pressure cube in cubelist).
p_ref_frac (bool, optional) – If True, levels are used as fractions of the surface pressure.
const (aeolus.const.const.ConstContainer, optional) – Required if p_ref_frac=True. If not given, constants are attempted to be retrieved from attributes of a cube in the cube list.
interpolator (callable or None) – The interpolator to use when computing the interpolation. See relevel() docs for more.
model (aeolus.model.Model, optional) – Model class with relevant variable names.
include_pressure (bool, optional) – If True, include the pressure cube in the output.

Returns:

List of cubes interpolated to pressure level(s).

Return type:

iris.cube.CubeList

aeolus.coord.interp_to_cube_time(cube_src, cube_tgt, model=Model [99 fields])[source]

Interpolate cube_src to cube_tgt along the time dimension (model.t).

Linear interpolation is used. Forecast period is copied from cube_tgt.

Parameters:

cube_src (iris.cube.Cube) – Cube to interpolate.
cube_tgt (iris.cube.Cube) – Cube with time dimension to interpolate to.
model (aeolus.model.Model, optional) – Model class with relevant variable names.

Returns:

Cube with the time dimension equal to cube_tgt.

Return type:

iris.cube.Cube

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

Get the nearest value of a coordinate.

Parameters:

cube (iris.cube.Cube) – Cube with the coordinate
coord_name (str or iris.coords.Coord) – Coordinate where to look the nearest point up
val (int or float) – The value to find

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=Model [99 fields])[source]

Regrid a cube in the horizontal and in the vertical.

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.

Return type:

iris.cube.Cube

aeolus.coord.replace_z_coord(cube, model=Model [99 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, add_shift=0, model=Model [99 fields])[source]

Take a cube spanning -180…180 degrees 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.
add_shift (int) – Additional shift of data (is not applied to the longitude coordinate).
model (aeolus.model.Model, optional) – Model class with a relevant longitude coordinate name.

Return type:

iris.cube.Cube