equations.py 文件源码

def temp_water(is_water, swir2, tirs1):
    """Use water to mask tirs and find 82.5 pctile

    Equation 7 and 8 (Zhu and Woodcock, 2012)

    Parameters
    ----------
    is_water: ndarray, boolean
        water mask, water is True, land is False
    swir2: ndarray
    tirs1: ndarray

    Output
    ------
    float:
        82.5th percentile temperature over water
    """
    # eq7
    th_swir2 = 0.03
    clearsky_water = is_water & (swir2 < th_swir2)

    # eq8
    clear_water_temp = tirs1.copy()
    clear_water_temp[~clearsky_water] = np.nan
    return np.nanpercentile(clear_water_temp, 82.5)