Python 中的 Haversine 公式(两个 GPS 点之间的方位和距离)
- 2024-12-12 08:41:00
- admin 原创
- 197
问题描述:
问题
我想知道如何获取两个 GPS 点之间的距离和方位。
我研究过半正弦距离。有人告诉我,我也可以使用相同的数据找到方位。
一切正常,但方位尚未完全正常工作。方位输出为负值,但应在 0 - 360 度之间。
设定的数据应该是水平方位96.02166666666666
,并且是:
Start point: 53.32055555555556, -1.7297222222222221
Bearing: 96.02166666666666
Distance: 2 km
Destination point: 53.31861111111111, -1.6997222222222223
Final bearing: 96.04555555555555
这是我的新代码:
from math import *
Aaltitude = 2000
Oppsite = 20000
lat1 = 53.32055555555556
lat2 = 53.31861111111111
lon1 = -1.7297222222222221
lon2 = -1.6997222222222223
lon1, lat1, lon2, lat2 = map(radians, [lon1, lat1, lon2, lat2])
dlon = lon2 - lon1
dlat = lat2 - lat1
a = sin(dlat/2)**2 + cos(lat1) * cos(lat2) * sin(dlon/2)**2
c = 2 * atan2(sqrt(a), sqrt(1-a))
Base = 6371 * c
Bearing = atan2(cos(lat1)*sin(lat2)-sin(lat1)*cos(lat2)*cos(lon2-lon1), sin(lon2-lon1)*cos(lat2))
Bearing = degrees(Bearing)
print ""
print ""
print "--------------------"
print "Horizontal Distance: "
print Base
print "--------------------"
print "Bearing: "
print Bearing
print "--------------------"
Base2 = Base * 1000
distance = Base * 2 + Oppsite * 2 / 2
Caltitude = Oppsite - Aaltitude
a = Oppsite/Base
b = atan(a)
c = degrees(b)
distance = distance / 1000
print "The degree of vertical angle is: "
print c
print "--------------------"
print "The distance between the Balloon GPS and the Antenna GPS is: "
print distance
print "--------------------"
解决方案 1:
以下是 Python 版本:
from math import radians, cos, sin, asin, sqrt
def haversine(lon1, lat1, lon2, lat2):
"""
Calculate the great circle distance in kilometers between two points
on the earth (specified in decimal degrees)
"""
# convert decimal degrees to radians
lon1, lat1, lon2, lat2 = map(radians, [lon1, lat1, lon2, lat2])
# haversine formula
dlon = lon2 - lon1
dlat = lat2 - lat1
a = sin(dlat/2)**2 + cos(lat1) * cos(lat2) * sin(dlon/2)**2
c = 2 * asin(sqrt(a))
r = 6371 # Radius of earth in kilometers. Use 3956 for miles. Determines return value units.
return c * r
解决方案 2:
这些答案大部分都是“四舍五入”地球半径。如果你用其他距离计算器(如 geopy)检查这些答案,这些函数就会失效。
效果很好:
from math import radians, cos, sin, asin, sqrt
def haversine(lat1, lon1, lat2, lon2):
R = 3959.87433 # this is in miles. For Earth radius in kilometers use 6372.8 km
dLat = radians(lat2 - lat1)
dLon = radians(lon2 - lon1)
lat1 = radians(lat1)
lat2 = radians(lat2)
a = sin(dLat/2)**2 + cos(lat1)*cos(lat2)*sin(dLon/2)**2
c = 2*asin(sqrt(a))
return R * c
# Usage
lon1 = -103.548851
lat1 = 32.0004311
lon2 = -103.6041946
lat2 = 33.374939
print(haversine(lat1, lon1, lat2, lon2))
解决方案 3:
还有一个矢量化的实现,它允许使用 4 个 NumPy 数组而不是标量值作为坐标:
def distance(s_lat, s_lng, e_lat, e_lng):
# Approximate radius of earth in km
R = 6373.0
s_lat = s_lat*np.pi/180.0
s_lng = np.deg2rad(s_lng)
e_lat = np.deg2rad(e_lat)
e_lng = np.deg2rad(e_lng)
d = np.sin((e_lat - s_lat)/2)**2 + np.cos(s_lat)*np.cos(e_lat) * np.sin((e_lng - s_lng)/2)**2
return 2 * R * np.arcsin(np.sqrt(d))
解决方案 4:
您可以尝试haversine包:
示例代码:
from haversine import haversine
haversine((45.7597, 4.8422), (48.8567, 2.3508), unit='mi')
输出:
243.71209416020253
解决方案 5:
方位计算不正确。您需要将输入交换为 atan2。
bearing = atan2(sin(long2 - long1)*cos(lat2), cos(lat1)*sin(lat2) - sin(lat1)*cos(lat2)*cos(long2 - long1))
bearing = degrees(bearing)
bearing = (bearing + 360) % 360
这将为您提供正确的方位。
解决方案 6:
这是@Michael Dunn 给出的 Haversine 公式的NumPy矢量化实现,比大矢量提高了 10-50 倍。
from numpy import radians, cos, sin, arcsin, sqrt
def haversine(lon1, lat1, lon2, lat2):
"""
Calculate the great circle distance between two points
on the earth (specified in decimal degrees)
"""
# Convert decimal degrees to radians:
lon1 = np.radians(lon1.values)
lat1 = np.radians(lat1.values)
lon2 = np.radians(lon2.values)
lat2 = np.radians(lat2.values)
# Implementing the haversine formula:
dlon = np.subtract(lon2, lon1)
dlat = np.subtract(lat2, lat1)
a = np.add(np.power(np.sin(np.divide(dlat, 2)), 2),
np.multiply(np.cos(lat1),
np.multiply(np.cos(lat2),
np.power(np.sin(np.divide(dlon, 2)), 2))))
c = np.multiply(2, np.arcsin(np.sqrt(a)))
r = 6371
return c*r
解决方案 7:
考虑到您的目标是测量两点之间的距离(以地理坐标表示),将留下以下三个选项:
半正矢公式
使用GeoPy测地距离
使用GeoPy大圆距离
选项 1
半正矢公式可以完成这项工作。但是,需要注意的是,这样做会将地球近似为球体,而这会产生误差(参见此答案)——因为地球不是球体。
为了使用半正矢公式,首先需要定义地球的半径。这本身可能会引起一些争议。考虑以下三个来源
美国宇航局戈达德太空飞行中心:6371公里
维基百科:6371 公里(3958.8 英里)
谷歌- 6371 公里
我将使用6371公里这个值作为地球半径的参考。
# Radius of the Earth
r = 6371.0
我们将利用math
模块。
了解了半径之后,我们转到坐标,然后开始将坐标转换为弧度,以便使用数学的三角函数。为此,它导入math.radians(x)
并使用它们,如下所示:
# Import radians from the 'math' module
from math import radians
# Latitude and longitude for the first point (let's consider 40.000º and 21.000º)
lat1 = radians(40.000)
lon1 = radians(21.000)
# Latitude and longitude for the second point (let's consider 30.000º and 25.000º)
lat2 = radians(30.000)
lon2 = radians(25.000)
现在就可以应用半正矢公式了。首先,用点 1 的经度减去点 2 的经度
dlon = lon2 - lon1
dlat = lat2 - lat1
然后,这里有几个三角函数需要用到,更具体地说math.sin()
, 、math.cos()
和math.atan2()
。我们还将使用math.sqrt()
# Import sin, cos, atan2, and sqrt from the 'math' module
from math import sin, cos, atan2, sqrt
a = sin(dlat / 2)**2 + cos(lat1) * cos(lat2) * sin(dlon / 2)**2
c = 2 * atan2(sqrt(a), sqrt(1 - a))
d = r * c
然后通过打印得到距离d
。
因为这可能会有所帮助,让我们将所有内容集中在一个函数中(受到Michael Dunn 的回答的启发)
from math import radians, cos, sin, atan2, sqrt
def haversine(lon1, lat1, lon2, lat2):
"""
Calculate the great-circle distance (in km) between two points
using their longitude and latitude (in degrees).
"""
# Radius of the Earth
r = 6371.0
# Convert degrees to radians
# First point
lat1 = radians(lat1)
lon1 = radians(lon1)
# Second point
lat2 = radians(lat2)
lon2 = radians(lon2)
# Haversine formula
dlon = lon2 - lon1
dlat = lat2 - lat1
a = sin(dlat / 2)**2 + cos(lat1) * cos(lat2) * sin(dlon / 2)**2
c = 2 * atan2(sqrt(a), sqrt(1 - a))
return r * c
选项 2
人们将使用GeoPy 的距离,更具体地说,geodesic
。
我们可以获得以公里或英里为单位的结果(来源)
# Import Geopy's distance
from geopy import distance
wellington = (-41.32, 174.81)
salamanca = (40.96, -5.50)
print(distance.distance(wellington, salamanca).km) # If one wants it in miles, change `km` to `miles`
[Out]: 19959.6792674
选项 3
人们将使用GeoPy 的距离,更具体地说,great-circle
。
我们可以获得以公里或英里为单位的结果(来源)
# Import Geopy's distance
from geopy import distance
newport_ri = (41.49008, -71.312796)
cleveland_oh = (41.499498, -81.695391)
print(distance.great_circle(newport_ri, cleveland_oh).miles) # If one wants it in km, change `miles` to `km`
[Out]: 536.997990696
笔记:
由于大圆距离通常使用 Haversine 公式计算(正如 Willem Hendriks 所指出的),选项 1 和 3 类似,但使用不同的半径。
+ GeoPy 的大圆距离使用地球的球形模型,使用国际大地测量学和地球物理联合会定义的平均地球半径,`6371.0087714150598 kilometers`约为`6371.009 km`(对于`WGS-84`),导致误差高达约`0.5%`[来源]。
解决方案 8:
您可以通过添加 360° 来解决负方位角问题。不幸的是,这可能会导致正方位角大于 360°。这非常适合使用模数运算符,因此总的来说,您应该添加以下行
Bearing = (Bearing + 360) % 360
在您的方法结束时。
解决方案 9:
请参阅Vincenty 与大圆距离计算之间的差异。
这实际上给出了两种获取距离的方法。它们是半正弦和 Vincentys。从我的研究中,我发现 Vincentys 相对准确。还可以使用import语句来实现。
解决方案 10:
默认情况下,atan2 中的 Y 是第一个参数。这是文档。您需要切换输入以获取正确的方位角。
bearing = atan2(sin(lon2-lon1)*cos(lat2), cos(lat1)*sin(lat2)-sin(lat1)*cos(lat2)*cos(lon2-lon1))
bearing = degrees(bearing)
bearing = (bearing + 360) % 360
解决方案 11:
这里有两个函数用于计算距离和方位,它们基于之前消息中的代码以及Python 中两点之间的罗盘方位(为了清晰起见,我为这两个函数添加了纬度、经度格式的地理点元组类型)。我测试了这两个函数,它们似乎工作正常。
# Encoding: UTF-8
from math import radians, cos, sin, asin, sqrt, atan2, degrees
def haversine(pointA, pointB):
if (type(pointA) != tuple) or (type(pointB) != tuple):
raise TypeError("Only tuples are supported as arguments")
lat1 = pointA[0]
lon1 = pointA[1]
lat2 = pointB[0]
lon2 = pointB[1]
# Convert decimal degrees to radians
lat1, lon1, lat2, lon2 = map(radians, [lat1, lon1, lat2, lon2])
# Haversine formula
dlon = lon2 - lon1
dlat = lat2 - lat1
a = sin(dlat/2)**2 + cos(lat1) * cos(lat2) * sin(dlon/2)**2
c = 2 * asin(sqrt(a))
r = 6371 # Radius of earth in kilometers. Use 3956 for miles
return c * r
def initial_bearing(pointA, pointB):
if (type(pointA) != tuple) or (type(pointB) != tuple):
raise TypeError("Only tuples are supported as arguments")
lat1 = radians(pointA[0])
lat2 = radians(pointB[0])
diffLong = radians(pointB[1] - pointA[1])
x = sin(diffLong) * cos(lat2)
y = cos(lat1) * sin(lat2) -
(sin(lat1) * cos(lat2) * cos(diffLong))
initial_bearing = atan2(x, y)
# Now we have the initial bearing but math.atan2 return values
# from -180° to + 180° which is not what we want for a compass bearing
# The solution is to normalize the initial bearing as shown below
initial_bearing = degrees(initial_bearing)
compass_bearing = (initial_bearing + 360) % 360
return compass_bearing
pA = (46.2038, 6.1530)
pB = (46.449, 30.690)
print haversine(pA, pB)
print initial_bearing(pA, pB)
解决方案 12:
你可以在 Python 中使用以下实现
import math
def haversine_distance(lat1, lon1, lat2, lon2, unit='K'):
r = 6371 # radius of the earth in kilometers
if unit == 'M':
r = 3960 # radius of the earth in miles
dLat = math.radians(lat2 - lat1)
dLon = math.radians(lon2 - lon1)
a = math.sin(dLat / 2) * math.sin(dLat / 2) + \n math.cos(math.radians(lat1)) * math.cos(math.radians(lat2)) * \n math.sin(dLon / 2) * math.sin(dLon / 2)
c = 2 * math.atan2(math.sqrt(a), math.sqrt(1 - a))
distance = r * c
return distance
您可以在Haversine Formula中阅读更多相关信息