Metview

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- new functions/methods on Fieldset to give an overview of contents:
- fs.describe()
- fs.describe("tp")
- fs.ls()
- see Jupyter notebook example at https://metview.readthedocs.io/en/latest/notebook_gallery.html
- new GRIB filtering function, select(), offers different filtering options from read() and is faster
- see Jupyter notebook example at https://metview.readthedocs.io/en/latest/notebook_gallery.html
- new shorthand way to select parameters from Fieldsets, e.g.
- g = fs["t"]
- g = fs["t500"]
- g = fs["t500hPa"]
- the Fieldset constructor can now take a list of paths to GRIB files or a wildcard:
- e.g. a = mv.Fieldset(path=["/path1/to/data1.grib", "relpath/data2.grib"])
- e.g. a = mv.Fieldset(path="data/*.grib")
- the result of a call to mcont() etc can now be modified, e.g.
- c = mv.mcont() ; c["contour_line_colour"] = "green" ; mv.plot(data, c)
- gv.update({"MAP_COASTLINE_land_SHADE_COLOUR": "green"}, sub="COASTlines")
- improved the output of print(Fieldset):
- "Fieldset (6 fields)"

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- new argument to setoutput(plot_widget=) - default True, set False to allow images to be saved into the notebook
- multi-page plots in Jupyter notebooks now contain the animation controls by default

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- added automatic play and speed controls to animated plots in Jupyter notebooks

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- added animate=True argument to plot() command for animated plots in Jupyter notebooks
- allowed cfgrib backend keyword arguments to be passed to Fieldset.to_dataset()
- Fieldset out-of-range indexing now raises an IndexError
- Fieldset merge() function now allows a single Fieldset as argument

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- renamed function download_gallery_data() to metview.gallery.load_dataset()

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- added new function download_gallery_data() to download Gallery example data files
- added write(filename) method for classes Fieldset, Geopoints, GeopointSet, Bufr and NetCDF
- added ability to construct a Fieldset from a list of Fieldsets: Fieldset([f1, f2, f3])
- added metzoom function (for the future)
- added keyword arguments to setoutput('jupyter') to control output size in notebooks
- added metview_python member to result of version_info() function