timelib.py 文件源码

def jd2dt(jd):
    """Convert julian date to datetime
    """
    n = int(round(float(jd)))
    a = n + 32044
    b = (4*a + 3)//146097
    c = a - (146097*b)//4
    d = (4*c + 3)//1461
    e = c - (1461*d)//4
    m = (5*e + 2)//153
    day = e + 1 - (153*m + 2)//5
    month = m + 3 - 12*(m//10)
    year = 100*b + d - 4800 + m/10

    tfrac = 0.5 + float(jd) - n
    tfrac_s = 86400.0 * tfrac 
    minfrac, hours = np.modf(tfrac_s / 3600.)
    secfrac, minutes = np.modf(minfrac * 60.)
    microsec, seconds = np.modf(secfrac * 60.)

    return datetime(year, month, day, int(hours), int(minutes), int(seconds), int(microsec*1E6))

#This has not been tested