regionmask.Regions.mask

Regions.mask(lon_or_obj, lat=None, *, lon_name=None, lat_name=None, method=None, wrap_lon=None, flag='abbrevs', use_cf=None)

create a 2D float mask of a set of regions for the given lat/ lon grid

Parameters:

lon_or_objobject or array_like

Can either be a longitude array and then lat needs to be given. Or an object where the longitude and latitude can be retrieved from, either using cf_xarray or by the names “lon” and “lat”. See also use_cf.

latarray_like, optional

If lon_or_obj is a longitude array, the latitude needs to be passed.

wrap_lonNone | bool | 180 | 360, default: None

Whether to wrap the longitude around, inferred automatically. If the regions and the provided longitude do not have the same base (i.e. one is -180..180 and the other 0..360) one of them must be wrapped. This can be achieved with wrap_lon:

None: autodetects whether the longitude needs to be wrapped
False: nothing is done. This is useful when working with coordinates that are not in lat/ lon format.
True: longitude data is wrapped to [0, 360[ if its minimum is smaller than 0 and wrapped to [-180, 180[ if its maximum is larger than 180.
180: Wraps longitude coordinates to [-180, 180[
360: Wraps longitude coordinates to [0, 360[

flagstr, default: “abbrevs”

Indicates if the “abbrevs” (abbreviations) or “names” should be added as flag_values and flag_meanings to the attributes (attrs) of the mask. If None nothing is added. Using cf_xarray these can be used to select single (mask.cf == "CNA") or multiple (mask.cf.isin) regions. Note that spaces are replaced by underscores.

use_cfbool, default: None

Whether to use cf_xarray to infer the names of the x and y coordinates. If None uses cf_xarray if the coord names are unambiguous. If True requires cf_xarray if False does not use cf_xarray.

Returns:

mask_2Dfloat xarray.DataArray