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cmip_branded_variable_mapper.horizontal_label#

Determination of the horizontal label

Functions:

Name Description
get_horizontal_label

Get horizontal label

get_horizontal_label #

get_horizontal_label(
    dimensions: tuple[str, ...], fallback: str = "hm"
) -> str

Get horizontal label

The logic this should follow is defined in Table F3 of Taylor et al.. This was last checked on September 24 2025. If updates have been made since, this code may be out of date with the underlying specification.

Parameters:

Name Type Description Default
dimensions tuple[str, ...]

Dimensions of the variable

 required
fallback str

Value to return if no other conditions are matched

 'hm'

Returns:

Type Description
str

horizontal label to use for constructing the branded variable name
Source code in src/cmip_branded_variable_mapper/horizontal_label.py 
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def get_horizontal_label(
    dimensions: tuple[str, ...],
    fallback: str = "hm",
) -> str:
    """
    Get horizontal label

    The logic this should follow is defined in Table F3 of
    [Taylor et al.](https://docs.google.com/document/d/19jzecgymgiiEsTDzaaqeLP6pTvLT-NzCMaq-wu-QoOc/edit?pli=1&tab=t.0).
    This was last checked on September 24 2025.
    If updates have been made since,
    this code may be out of date with the underlying specification.

    Parameters
    ----------
    dimensions
        Dimensions of the variable

    fallback
        Value to return if no other conditions are matched

    Returns
    -------
    :
        horizontal label to use for constructing the branded variable name
    """
    # The logic of Table F3 is pretty hard to follow
    # so we've gone for a verbose, but extremely clear implementation below
    # rather than trying to do something fancier.
    longitude_present = "longitude" in dimensions
    latitude_present = "latitude" in dimensions
    if (
        (longitude_present and latitude_present)
        or ("xant" in dimensions and "yant" in dimensions)
        or ("xgre" in dimensions and "ygre" in dimensions)
    ):
        return "hxy"

    basin_present = "basin" in dimensions
    if latitude_present and not (longitude_present or basin_present):
        return "hy"

    if "site" in dimensions:
        return "hs"

    if latitude_present and basin_present:
        return "hyb"

    if (
        "oline" in dimensions
        or "siline" in dimensions
        or ("gridlatitude" in dimensions and basin_present)
    ):
        return "ht"

    return fallback