根据经纬度计算距离

def haversine(lat1, lon1, lat2, lon2): # 经度1，纬度1，经度2，纬度2 （十进制度数）
    """
    Calculate the great circle distance between two points
    on the earth (specified in decimal degrees)
    """
    # 将十进制度数转化为弧度
    lon1, lat1, lon2, lat2 = float(lon1), float(lat1), float(lon2), float(lat2)
    lon1, lat1, lon2, lat2 = map(math.radians, [lon1, lat1, lon2, lat2])

    # haversine公式
    dlon = lon2 - lon1
    dlat = lat2 - lat1
    a = math.sin(dlat / 2) ** 2 + math.cos(lat1) * math.cos(lat2) * math.sin(dlon / 2) ** 2
    c = 2 * math.asin(math.sqrt(a))
    r = 6371 # 地球平均半径，单位为公里
    return c * r * 1000