Convert DD (decimal degrees) to DMS (degrees minut

问题:

How do you convert Decimal Degrees to Degrees Minutes Seconds In Python? Is there a Formula already written?

回答1:

This is exactly what divmod was invented for:

>>> def decdeg2dms(dd):
...   mnt,sec = divmod(dd*3600,60)
...   deg,mnt = divmod(mnt,60)
...   return deg,mnt,sec

>>> dd = 45 + 30.0/60 + 1.0/3600
>>> print dd
45.5002777778
>>> decdeg2dms(dd)
(45.0, 30.0, 1.0)

回答2:

Here is my updated version based upon Paul McGuire's. This one should handle negatives correctly.

def decdeg2dms(dd):
   is_positive = dd >= 0
   dd = abs(dd)
   minutes,seconds = divmod(dd*3600,60)
   degrees,minutes = divmod(minutes,60)
   degrees = degrees if is_positive else -degrees
   return (degrees,minutes,seconds)

回答3:

If you want to handle negatives properly, the first non-zero measure is set negative. It is counter to common practice to specify all of degrees, minutes and seconds as negative (Wikipedia shows 40° 26.7717, -79° 56.93172 as a valid example of degrees-minutes notation, in which degrees are negative and minutes have no sign), and setting degrees as negative does not have any effect if the degrees portion is 0. Here is a function that adequately handles this, based on Paul McGuire's and baens' functions:

def decdeg2dms(dd):
    negative = dd < 0
    dd = abs(dd)
    minutes,seconds = divmod(dd*3600,60)
    degrees,minutes = divmod(minutes,60)
    if negative:
        if degrees > 0:
            degrees = -degrees
        elif minutes > 0:
            minutes = -minutes
        else:
            seconds = -seconds
    return (degrees,minutes,seconds)

回答4:

Just a couple of * 60 multiplications and a couple of int truncations, i.e.:

>>> decdegrees = 31.125
>>> degrees = int(decdegrees)
>>> temp = 60 * (decdegrees - degrees)
>>> minutes = int(temp)
>>> seconds = 60 * (temp - minutes)
>>> print degrees, minutes, seconds
31 7 30.0
>>> 

回答5:

This is my Python code:

def DecimaltoDMS(Decimal):
d = int(Decimal)
m = int((Decimal - d) * 60)
s = (Decimal - d - m/60) * 3600.00
z= round(s, 2)
if d >= 0:
    print ("N ", abs(d), "º ", abs(m), "' ", abs(z), '" ')
else:
    print ("S ", abs(d), "º ", abs(m), "' ", abs(z), '" ')

回答6:

The sign has better be returned separately, so that it can be used to choose from ('N', 'S') or ('E', 'W'), for example.

import math

def dd_to_dms(degs):
    neg = degs < 0
    degs = (-1) ** neg * degs
    degs, d_int = math.modf(degs)
    mins, m_int = math.modf(60 * degs)
    secs        =           60 * mins
    return neg, d_int, m_int, secs

回答7:

Improving @chqrlie answer:

    def deg_to_dms(deg, type='lat'):
        decimals, number = math.modf(deg)
        d = int(number)
        m = int(decimals * 60)
        s = (deg - d - m / 60) * 3600.00
        compass = {
            'lat': ('N','S'),
            'lon': ('E','W')
        }
        compass_str = compass[type][0 if d >= 0 else 1]
        return '{}º{}\'{:.2f}"{}'.format(abs(d), abs(m), abs(s), compass_str)

回答8:

Use fmod and rounding to get the degrees and fraction separated. Multiply the fraction by 60 and repeat to get minutes and a remainder. Then multiply that last part by 60 again to get the number of seconds.