iris.coord_categorisation

Cube functions for coordinate categorisation.

All the functions provided here add a new coordinate to a cube.

• The function add_categorised_coord() performs a generic coordinate categorisation.
• The other functions all implement specific common cases (e.g. add_day_of_month()). Currently, these are all calendar functions, so they only apply to “Time coordinates”.

In this module:

• add_categorised_coord
• add_day_of_month
• add_day_of_year
• add_month
• add_month_fullname
• add_month_number
• add_season
• add_season_membership
• add_season_number
• add_season_year
• add_weekday
• add_weekday_fullname
• add_weekday_number
• add_year

iris.coord_categorisation.add_categorised_coord(cube, name, from_coord, category_function, units='1')

Add a new coordinate to a cube, by categorising an existing one.

Make a new iris.coords.AuxCoord from mapped values, and add it to the cube.

Args:

• cube (iris.cube.Cube):

  the cube containing ‘from_coord’. The new coord will be added into it.

• name (string):

  name of the created coordinate

• from_coord (iris.coords.Coord or string):

  coordinate in ‘cube’, or the name of one

• category_function (callable):

  function(coordinate, value), returning a category value for a coordinate point-value

Kwargs:

• units:

  units of the category value, typically ‘no_unit’ or ‘1’.

↑ top ↑

iris.coord_categorisation.add_day_of_month(cube, coord, name='day_of_month')

Add a categorical day-of-month coordinate, values 1..31.

↑ top ↑

iris.coord_categorisation.add_day_of_year(cube, coord, name='day_of_year')

Add a categorical day-of-year coordinate, values 1..365 (1..366 in leap years).

↑ top ↑

iris.coord_categorisation.add_month(cube, coord, name='month')

Add a categorical month coordinate, values ‘Jan’..’Dec’.

↑ top ↑

iris.coord_categorisation.add_month_fullname(cube, coord, name='month_fullname')

Add a categorical month coordinate, values ‘January’..’December’.

↑ top ↑

iris.coord_categorisation.add_month_number(cube, coord, name='month_number')

Add a categorical month coordinate, values 1..12.

↑ top ↑

iris.coord_categorisation.add_season(cube, coord, name='season', seasons=('djf', 'mam', 'jja', 'son'))

Add a categorical season-of-year coordinate, with user specified seasons.

Args:

• cube (iris.cube.Cube):

  The cube containing ‘coord’. The new coord will be added into it.

• coord (iris.coords.Coord or string):

  Coordinate in ‘cube’, or its name, representing time.

Kwargs:

• name (string):

  Name of the created coordinate. Defaults to “season”.

• seasons (list of strings):

  List of seasons defined by month abbreviations. Each month must appear once and only once. Defaults to standard meteorological seasons (‘djf’, ‘mam’, ‘jja’, ‘son’).

↑ top ↑

iris.coord_categorisation.add_season_membership(cube, coord, season, name='season_membership')

Add a categorical season membership coordinate for a user specified season.

The coordinate has the value True for every time that is within the given season, and the value False otherwise.

Args:

• cube (iris.cube.Cube):

  The cube containing ‘coord’. The new coord will be added into it.

• coord (iris.coords.Coord or string):

  Coordinate in ‘cube’, or its name, representing time.

• season (string):

  Season defined by month abbreviations.

Kwargs:

• name (string):

  Name of the created coordinate. Defaults to “season_membership”.

↑ top ↑

iris.coord_categorisation.add_season_number(cube, coord, name='season_number', seasons=('djf', 'mam', 'jja', 'son'))

Add a categorical season-of-year coordinate, values 0..N-1 where N is the number of user specified seasons.

Args:

• cube (iris.cube.Cube):

  The cube containing ‘coord’. The new coord will be added into it.

• coord (iris.coords.Coord or string):

  Coordinate in ‘cube’, or its name, representing time.

Kwargs:

• name (string):

  Name of the created coordinate. Defaults to “season_number”.

• seasons (list of strings):

  List of seasons defined by month abbreviations. Each month must appear once and only once. Defaults to standard meteorological seasons (‘djf’, ‘mam’, ‘jja’, ‘son’).

↑ top ↑

iris.coord_categorisation.add_season_year(cube, coord, name='season_year', seasons=('djf', 'mam', 'jja', 'son'))

Add a categorical year-of-season coordinate, with user specified seasons.

Args:

• cube (iris.cube.Cube):

  The cube containing ‘coord’. The new coord will be added into it.

• coord (iris.coords.Coord or string):

  Coordinate in ‘cube’, or its name, representing time.

Kwargs:

• name (string):

  Name of the created coordinate. Defaults to “season_year”.

• seasons (list of strings):

  List of seasons defined by month abbreviations. Each month must appear once and only once. Defaults to standard meteorological seasons (‘djf’, ‘mam’, ‘jja’, ‘son’).

↑ top ↑

iris.coord_categorisation.add_weekday(cube, coord, name='weekday')

Add a categorical weekday coordinate, values ‘Mon’..’Sun’.

↑ top ↑

iris.coord_categorisation.add_weekday_fullname(cube, coord, name='weekday_fullname')

Add a categorical weekday coordinate, values ‘Monday’..’Sunday’.

↑ top ↑

iris.coord_categorisation.add_weekday_number(cube, coord, name='weekday_number')

Add a categorical weekday coordinate, values 0..6 [0=Monday].

↑ top ↑

iris.coord_categorisation.add_year(cube, coord, name='year')

Add a categorical calendar-year coordinate.