nearest_gridpoint

nearest_gridpoint(fs, gpt[, mode])

Returns the nearest gridpoint value from fs for a given location (or locations).

Parameters

fs (Fieldset) – input fieldset
lats (number or ndarray) – target latitude(s)
lons (number or ndarray) – target longitudes(s)
location (list) – single target location defined as a list of [lat, lon]
gpt (Geopoints) – input geopoints
mode (str) – specifies the way missing values are handled. The only allowed value is “valid”.

Return type

number or list or ndarray or Geopoints

fs must be a gridded field.

The nearest gridpoint extraction depends on the arguments:

location defines a single location. The return value is a number when fs only contains one field, and list otherwise.
lats and lons can define either a single location (as number) or multiple locations (as ndarray). If a single location is specified the return value is the same as for location. For multiple locations an ndarray is returned.
when gpt is specified only the first field of fs is used. The result is a Geopoints containing the the nearest gridpoint values for all the locations in gpt. Where it is not possible to generate a sensible value due to lack of valid data in fs, the internal geopoints missing value is used (this value can be checked for with the built-in variable geo_missing_value or removed with the function remove_missing_values()).

Parameter mode controls the return value when the nearest gridpoint value is a missing value or the location is out of the grid area:

by default, None is returned for a single location and nan for multiple locations.
if mode is ‘valid’ then from out of the surrounding gridpoints the nearest valid one is returned; None or nan will still be returned if all the surrounding points are missing.

Note