我有一个用起点和终点定义的线段:
A:
x1 = 10.7196405787775
y1 = 59.9050401935882
B:
x2 = 10.7109989561813
y2 = 59.9018650448204
其中x定义经度,y定义纬度.
我也有一点意见:
P:
x0 = 10.6542116666667
y0 = 59.429105
如何计算线段与点之间的最短距离?我知道如何在笛卡尔坐标中执行此操作,但不能在长/纬度坐标中执行此操作.
最佳答案 使用有用的Python地理编码库
geopy,以及从
Chris Veness’s geodesy formulae开始的大圆中点的公式,我们可以找到一个大圆弧和给定点之间的距离:
from math import sin, cos, atan2, sqrt, degrees, radians, pi
from geopy.distance import great_circle as distance
from geopy.point import Point
def midpoint(a, b):
a_lat, a_lon = radians(a.latitude), radians(a.longitude)
b_lat, b_lon = radians(b.latitude), radians(b.longitude)
delta_lon = b_lon - a_lon
B_x = cos(b_lat) * cos(delta_lon)
B_y = cos(b_lat) * sin(delta_lon)
mid_lat = atan2(
sin(a_lat) + sin(b_lat),
sqrt(((cos(a_lat) + B_x)**2 + B_y**2))
)
mid_lon = a_lon + atan2(B_y, cos(a_lat) + B_x)
# Normalise
mid_lon = (mid_lon + 3*pi) % (2*pi) - pi
return Point(latitude=degrees(mid_lat), longitude=degrees(mid_lon))
在这个例子中给出了:
# Example:
a = Point(latitude=59.9050401935882, longitude=10.7196405787775)
b = Point(latitude=59.9018650448204, longitude=10.7109989561813)
p = Point(latitude=59.429105, longitude=10.6542116666667)
d = distance(midpoint(a, b), p)
print d.km
# 52.8714586903