wrap longitude to 180/ 360

wrap_lon.py

import numpy as np


def wrap360(obj, lon='lon'):
    """
    wrap longitude coordinates to 0..360

    Parameters
    ----------
    obj : xr.Dataset or xr.DataArray
        object with longitude coordinates
    lon : str, default: "lon"
        name of the longitude ('lon', 'longitude', ...)

    Returns
    -------
    wrapped : Dataset
        Another dataset array wrapped around.
    """

    # wrap -180..179 to 0..359   

    
    new_lon = np.mod(obj[lon], 360)

    obj = obj.assign_coords(**{lon: new_lon})
    # sort the data
    return obj.reindex(**{lon : np.sort(obj[lon])})



def wrap180(obj, lon='lon'):
    """
    wrap longitude coordinates to -180..180

    Parameters
    ----------
    obj : xr.Dataset or xr.DataArray
        object with longitude coordinates
    lon : str, default: "lon"
        name of the longitude ('lon', 'longitude', ...)

    Returns
    -------
    wrapped : Dataset
        Another dataset array wrapped around.
    """

    # wrap 0..359 to -180..179
    new_lon = obj[lon].data

    # only modify values > 180
    sel = new_lon > 180
    
    if np.any(sel):
        # 359 -> -1, 181 -> -179    
        new_lon[sel] = np.mod(new_lon[sel], -180)
        obj = obj.assign_coords(**{lon: new_lon})
        # sort the data

    obj = obj.reindex(**{lon : np.sort(obj[lon])})
    
    return obj