根据经纬度计算两点间距离

# 根据经纬度计算两点间距离
# 经度 long  纬度 lat
def GetDistance( lng1,  lat1,  lng2,  lat2):
    u'''''计算两点间球面距离 单位为m'''
    EARTH_RADIUS = 6378.137 # 地球周长/2*pi 此处地球周长取40075.02km pi=3.1415929134165665
    from math import asin,sin,cos,acos,radians, degrees,pow,sqrt, hypot,pi

    # 方法0
    # 最简单的求平面两点间距离 误差比较大
    d=hypot(lng2-lng1,lat2-lat1)*40075.02/360*1000
    print 'd0=',d

    # 方法1
    #  '''  d＝111.12cos{1/[sinΦAsinΦB+cosΦAcosΦBcos(λB—λA)]}    '''
    # ''' 其中A点经度、纬度分别为λA和ΦA，B点的经度、纬度分别为λB和ΦB，d为距离。'''
    m=cos(radians(lat1))*cos(radians(lat2))*cos(radians(lng2-lng1))
    x=1/(sin(radians(lat1))*sin(radians(lat2)) +m)
    d=111.12*cos(radians(1/x))
    print 'd1=',d

    # 方法2
    # 据说来源于 google maps 的脚本
    # 见 http://en.wikipedia.org/wiki/Great-circle_distance 中的 haversine
    radLat1 = radians(lat1) # a点纬度(单位是弧度)
    radLat2 = radians(lat2) # b点纬度(单位是弧度
    a = radLat1 - radLat2 # 两点间的纬度弧度差
    b = radians(lng1) - radians(lng2) # 两点间的经度弧度差
    s = 2 * asin(sqrt(pow(sin(a/2),2) + cos(radLat1)*cos(radLat2)*pow(sin(b/2),2))) # 两点间的弧度
    s = s * EARTH_RADIUS
#   s = round(s * 10000) / 10000 # 四舍五入保留小数点后4位
    d=s*1000
    print 'd2=',d

    # 方法3
    # ''' 经纬坐标为P(x1,y1) Q(x2,y2) '''
    #   D=arccos[cosy1*cosy2*cos(x1-x2)+siny1*siny2]*2*PI*R/360
    d=acos(cos(radians(lat1))*cos(radians(lat2))*cos(radians(lng1-lng2))+sin(radians(lat1))*sin(radians(lat2)))*EARTH_RADIUS*1000
    print 'd3=',d

    return d
GetDistance(116.95400,39.95400,116.95300,39.95300)