#!/usr/bin/env python
# -*- coding: utf-8 -*-
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"""Script to run neighbourhood processing."""
from improver import cli
from improver.constants import DEFAULT_PERCENTILES
[docs]@cli.clizefy
@cli.with_output
def process(
cube: cli.inputcube,
mask: cli.inputcube = None,
*,
neighbourhood_output,
neighbourhood_shape="square",
radii: cli.comma_separated_list,
lead_times: cli.comma_separated_list = None,
degrees_as_complex=False,
weighted_mode=False,
area_sum=False,
percentiles: cli.comma_separated_list = DEFAULT_PERCENTILES,
halo_radius: float = None,
):
"""Runs neighbourhood processing.
Apply the requested neighbourhood method via the
NeighbourhoodProcessing plugin to a Cube.
Args:
cube (iris.cube.Cube):
The Cube to be processed, usually a thresholded data set.
mask (iris.cube.Cube):
A cube to mask the input cube. The data should contain 1 for
usable points and 0 for discarded points.
Can't be used with "percentiles" as neighbourhood_output (Optional)
neighbourhood_output (str):
The form of the results generated using neighbourhood processing.
If "probabilities" is selected, the mean probability with a
neighbourhood is calculated. If "percentiles" is selected, then
the percentiles are calculated with a neighbourhood. Calculating
percentiles from a neighbourhood is only supported for a circular
neighbourhood, and the input cube should be ensemble realizations.
The calculation of percentiles from a neighbourhood is notably slower
than neighbourhood processing using a thresholded probability field.
Options: "probabilities", "percentiles".
neighbourhood_shape (str):
Name of the neighbourhood method to use. Only a "circular"
neighbourhood shape is applicable for calculating "percentiles"
output.
Options: "circular", "square".
Default: "square".
radii (list of float):
The radius or a list of radii in metres of the neighbourhood to
apply.
If it is a list, it must be the same length as lead_times, which
defines at which lead time to use which nbhood radius. The radius
will be interpolated for intermediate lead times.
lead_times (list of int):
The lead times in hours that correspond to the radii to be used.
If lead_times are set, radii must be a list the same length as
lead_times.
degrees_as_complex (bool):
Include this option to process angles as complex numbers.
Not compatible with circular kernel or percentiles.
weighted_mode (bool):
Include this option to set the weighting to decrease with radius.
Otherwise a constant weighting is assumed.
weighted_mode is only applicable for calculating "probability"
neighbourhood output using the circular kernel.
area_sum (bool):
Return sum rather than fraction over the neighbourhood area.
percentiles (float):
Calculates value at the specified percentiles from the
neighbourhood surrounding each grid point. This argument has no
effect if the output is probabilities.
halo_radius (float):
Set this radius in metres to define the excess halo to clip. Used
where a larger grid was defined than the standard grid and we want
to clip the grid back to the standard grid. Otherwise no clipping
is applied.
Returns:
iris.cube.Cube:
A processed Cube.
Raises:
RuntimeError:
If weighted_mode is used with the wrong neighbourhood_output.
RuntimeError:
If degree_as_complex is used with
neighbourhood_output='percentiles'.
RuntimeError:
If degree_as_complex is used with neighbourhood_shape='circular'.
"""
from improver.nbhood import radius_by_lead_time
from improver.nbhood.nbhood import (
GeneratePercentilesFromANeighbourhood,
NeighbourhoodProcessing,
)
from improver.utilities.pad_spatial import remove_cube_halo
from improver.wind_calculations.wind_direction import WindDirection
if neighbourhood_output == "percentiles":
if weighted_mode:
raise RuntimeError(
"weighted_mode cannot be used with" 'neighbourhood_output="percentiles"'
)
if degrees_as_complex:
raise RuntimeError("Cannot generate percentiles from complex " "numbers")
if neighbourhood_shape == "circular":
if degrees_as_complex:
raise RuntimeError(
"Cannot process complex numbers with circular neighbourhoods"
)
if degrees_as_complex:
# convert cube data into complex numbers
cube.data = WindDirection.deg_to_complex(cube.data)
radius_or_radii, lead_times = radius_by_lead_time(radii, lead_times)
if neighbourhood_output == "probabilities":
result = NeighbourhoodProcessing(
neighbourhood_shape,
radius_or_radii,
lead_times=lead_times,
weighted_mode=weighted_mode,
sum_only=area_sum,
re_mask=True,
)(cube, mask_cube=mask)
elif neighbourhood_output == "percentiles":
result = GeneratePercentilesFromANeighbourhood(
radius_or_radii, lead_times=lead_times, percentiles=percentiles,
)(cube)
if degrees_as_complex:
# convert neighbourhooded cube back to degrees
result.data = WindDirection.complex_to_deg(result.data)
if halo_radius is not None:
result = remove_cube_halo(result, halo_radius)
return result