Source code for pycif.plugins.datastreams.fields.iconart_icbc.read

import pandas as pd
import numpy as np
import xarray as xr
from .....utils.check.errclass import CifError, CifKeyError
from .....utils.hdf5 import _hdf5_lock



def read(
        self,
        name,
        varnames,
        dates,
        files,
        interpol_flx=False,
        comp_type=None,
        ddi=None,
        **kwargs
):
    """Read ICON-ART initial/boundary condition data into a pyCIF DataArray.

    For ``comp_type == "inicond"``, reads the variable from the single
    file in ``files`` and adds a singleton (fake) latitude axis. For
    ``"lbc"``/``"background"``, reads the variable from each file in turn,
    selects the time slice matching the requested date, and stacks the
    results (also adding a singleton latitude axis).

    Args:
        self: The field/tracer Plugin.
        name: Name of the component (used as fallback variable name).
        varnames: Name of the variable to read; if empty, ``name`` is used
            instead.
        dates: List of date entries to extract, matching ``files``.
        files: List of files matching ``dates``.
        interpol_flx: Unused.
        comp_type: Type of file to read: ``"inicond"``, ``"lbc"`` or
            ``"background"``.
        ddi: Unused.
        **kwargs: Unused.

    Returns:
        xarray.DataArray: A 4-dimensional ``(time, lev, lat, lon)`` array
        with a singleton ``lat`` axis (ICON-ART's native grid is
        unstructured; the horizontal dimension is carried by ``lon``).

    Raises:
        CifError: If ``comp_type`` is ``None`` or not recognized.
        CifKeyError: If the requested date is not found in an
            ``lbc``/``background`` file.
    """

    var2extract = varnames if varnames != "" else name

    # Check the type of limit condition to check
    if comp_type is None:
        raise CifError(
            "Trying to read limit conditions for ICON-ART, "
            "but did not specify the type"
        )

    # Read initial conditions
    if comp_type == "inicond":

        ic_file = files[0]
        with _hdf5_lock:
            ds = xr.open_dataset(ic_file)
            data = ds[var2extract][:]

            # -- Add fake lat dimensions at the end
            data = data.values[:, :, np.newaxis, :]
        
        xmod = xr.DataArray(
            data,
            coords={"time": [np.min(dates)]},
            dims=("time", "lev", "lat", "lon"),
        )

    # Read Lateral boundary conditions
    elif comp_type in ["lbc", "background"]:
     
        trcr_lbc = []
        out_dates = []
        for dd, ff in zip(dates, files):

            # Getting the data
            with _hdf5_lock:
                ds = xr.open_dataset(ff)
                da = ds[var2extract]

            if dd[0] in pd.to_datetime(da.time):
                data = da.sel(time=dd[0])
            else:
                raise CifKeyError("Could not find the correct data in the lbc file")

            # Appending
            trcr_lbc.append(data)
            out_dates.append(dd[0])

        xout = np.array(trcr_lbc)[:, :, np.newaxis, :]

        # Putting the data into an xarray
        xmod = xr.DataArray(
            xout, coords={"time": out_dates}, dims=("time", "lev", "lat", "lon")
        )

            

    else:
        raise CifError(
            f"Could not recognize the type of file to read in ICONART: {comp_type}"
        )
    
    return xmod