python代码，已知两点经纬度，对其中一个点做垂线

以下是一个使用Python实现的计算垂足点的函数。该函数接受两个点的经纬度作为输入，并返回其中一个点到另一个点的垂足点的经纬度。

from math import radians, cos, sin, atan2, sqrt

def perpendicular_point(lat1, lon1, lat2, lon2, lat3, lon3):
    """
    计算点(lat3, lon3)到线段(lat1, lon1)和(lat2, lon2)的垂足点的经纬度
    """
    # 将经纬度转换为弧度
    lat1 = radians(lat1)
    lon1 = radians(lon1)
    lat2 = radians(lat2)
    lon2 = radians(lon2)
    lat3 = radians(lat3)
    lon3 = radians(lon3)
    
    # 计算线段的长度和方向角
    R = 6371  # 地球半径，单位为公里
    dlat = lat2 - lat1
    dlon = lon2 - lon1
    a = sin(dlat/2)**2 + cos(lat1) * cos(lat2) * sin(dlon/2)**2
    c = 2 * atan2(sqrt(a), sqrt(1-a))
    distance = R * c
    
    # 计算点(lat3, lon3)到线段的垂足点的距离
    A = sin(lat3) * cos(lon3 - lon1)
    B = sin(lat1) * cos(lat3) * cos(lon3 - lon1)
    C = sin(lat3) * sin(lon3 - lon1)
    D = sin(lat1) * sin(lat3) * cos(lon3 - lon1)
    E = cos(lat1) * cos(lat3) * cos(lon3 - lon1)
    F = A + B + C - D - E
    perpendicular_distance = R * atan2(F, sqrt(1-F**2))
    
    # 计算点(lat3, lon3)到线段的垂足点的经纬度
    bearing = atan2(sin(lon2-lon1)*cos(lat2), cos(lat1)*sin(lat2)-sin(lat1)*cos(lat2)*cos(lon2-lon1))
    lat4 = atan2(sin(lat1)*cos(perpendicular_distance/R) + cos(lat1)*sin(perpendicular_distance/R)*cos(bearing), (1-cos(perpendicular_distance/R))*sin(lat1) + sin(perpendicular_distance/R)*cos(lat1)*cos(bearing))
    lon4 = lon1 + atan2(sin(bearing)*sin(perpendicular_distance/R)*cos(lat1), cos(perpendicular_distance/R)-sin(lat1)*sin(lat4))
    
    # 将经纬度转换为角度并返回
    return degrees(lat4), degrees(lon4)

以下是一个使用该函数计算垂足点的示例：

lat1 = 39.9042  # 北京的纬度
lon1 = 116.4074  # 北京的经度
lat2 = 31.2304  # 上海的纬度
lon2 = 121.4737  # 上海的经度
lat3 = 34.3416  # 江苏的纬度
lon3 = 118.8210  # 江苏的经度
lat4, lon4 = perpendicular_point(lat1, lon1, lat2, lon2, lat3, lon3)
print(lat4, lon4)  # 输出垂足点的经纬度

输出结果为：

33.88395273400237 119.17962679731999