Useful functions

dropna(ds, nanval[, varname])	Drop values corrresponding to NaN (marthe convention, eg.
fillna(ds, value[, varname])	Replace real nan (np.nan) value in dataset[varname], edge case of gridmarthe.replace()
subset(ds, value[, varname])	Subset dataset based on variable name and value.
replace(ds, value, replace[, varname])	Replace a value in xr.Dataset for a variable
assign_coords(ds[, add_lay, coords, ...])	Assign coordinates from variables to dimensions
stack_coords(ds[, coords, dropna])	Transform a 3 or 4D aray into 1 or 2D array inverse of assign_coords()
read_dates_from_pastp(fpastp[, encoding])	Read simulation timesteps from a .pastp file
get_dims_from_attrs(ds)	Get Marthe grid dimensions from Dataset attributes
sel_by_coords(ds[, x, y, z, method, ...])	Filter a 1D flattened xarray Dataset by spatial (x, y) and/or z ranges.
slice_cross_section(grid[, x, y, agg_along_axis])	grid needs geom infos and to have x,y as dimension.