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Any Metview function that normally returns a vector will return a numPy array when called from Python. For example, the follownig fieldset functions return numPy arrays:

Code Block
languagepy
a = mv.read('my_data.grib') # returns a Fieldset
lats = mv.latitudes(a)      # returns a numPy array
lons = mv.longitudes(a)     # returns a numPy array
vals = mv.values(a)         # returns a numPy array

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The Fieldset object has an additional method, to_dataset(), which produces an xarray Dataset object from the given fieldset. This is an N-dimensional data array based on the Common Data Model used in netCDF. For example:

Code Block
languagepy
import metview as mv

t2m_fc = mv.retrieve(
	type    = 'fc',
	levtype = 'sfc',
	param   = ['2t', '2d'],
	date    = -5,
	step    = list(range(0, 48+1, 6)),
	grid    = [1,1]
)

xa = t2m_fc.to_dataset()
print(xa)

will produce the following output:

Code Block
languagetext
<xarray.Dataset>
Dimensions:    (latitude: 181, longitude: 360, step: 9, time: 1)
Coordinates:
  * time       (time) datetime64[ns] 2018-05-10T12:00:00
  * step       (step) timedelta64[ns] 0 days 00:00:00 0 days 06:00:00 ...
  * latitude   (latitude) float64 90.0 89.0 88.0 87.0 86.0 85.0 84.0 83.0 ...
  * longitude  (longitude) float64 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 ...
Data variables:
    2t         (time, step, latitude, longitude) float32 ...
    2d         (time, step, latitude, longitude) float32 ...
Attributes:
    Conventions:  CF-1.7
    comment:      GRIB to CF translation performed by xarray-grib

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