Source code for pycif.plugins.domains.chimere.read_domain

import numpy as np




def read_grid(domain, **kwargs):
    """Read the CHIMERE horizontal and vertical grid from pre-computed coordinate files.

    Reads ``domainlist.nml`` to determine grid dimensions (``nzo`` × ``nme``),
    then loads cell centres from ``HCOORD/COORD_{domid}`` and corners from
    ``HCOORD/COORDcorner_{domid}``.  Vertical sigma levels are read from
    ``VCOORD/VCOORD_{nlev}_{p1}_{pmax}`` and stored as ``sigma_a`` /
    ``sigma_b`` (in hPa).

    Sets on *domain*: ``nlon``, ``nlat``, ``nlev``, ``zlon``, ``zlat``,
    ``zlonc``, ``zlatc``, ``corners``, ``sigma_a``, ``sigma_b``.

    Args:
        domain: CHIMERE domain plugin instance with ``repgrid``, ``domid``,
            ``nlev``, ``p1``, and ``pmax`` set.
        **kwargs: unused.

    Raises:
        AttributeError: if ``domain.domid`` is not found in ``domainlist.nml``.
    """

    # Loading geometry from the list of existing domains
    nzo = 0
    nme = 0
    with open(f"{domain.repgrid}/domainlist.nml", "r") as fgrid:
        ln = fgrid.readlines()
        for l in ln[1:]:
            s = l.split()
            if s[0] == domain.domid:
                nzo = int(s[1])
                nme = int(s[2])
                break
    
    if nzo == nme == 0:
        raise AttributeError(f"Could not find the domain {domain.domid} in the domainlist file {domain.repgrid}")
    
    # Saving information to domain attributes
    domain.nlat = nme
    domain.nlon = nzo

    # Reading lat/lon and latc/lonc
    file_hcoord = f"{domain.repgrid}/HCOORD/COORD_{domain.domid}"
    data = np.genfromtxt(file_hcoord)
    lon = data[:, 0].reshape(nme, nzo)
    lat = data[:, 1].reshape(nme, nzo)

    file_hcoord = f"{domain.repgrid}/HCOORD/COORDcorner_{domain.domid}"
    data = np.genfromtxt(file_hcoord)
    lonc = data[:, 0].reshape(nme + 1, nzo + 1)
    latc = data[:, 1].reshape(nme + 1, nzo + 1)

    # Putting the data into the domain
    domain.zlonc = lonc
    domain.zlatc = latc
    domain.zlon = lon
    domain.zlat = lat
    domain.corners = f"{domain.repgrid}/HCOORD/COORDcorner_{domain.domid}"

    # Reading vertical coordinates
    file_vcoord = f"{domain.repgrid}/VCOORD/VCOORD_{domain.nlev}_{domain.p1}_{domain.pmax}"
    data = np.concatenate([[[0, 1]], np.genfromtxt(file_vcoord)], axis=0)
    domain.sigma_a = data[:, 0] * 1e3
    domain.sigma_b = data[:, 1]

    domain.nlev = len(domain.sigma_a) - 1