Python的Haversine函数数学库出错

Question

我试图找到两个地理拉特和多头之间的距离

我已经创建了一个具有必要公式的函数hasrsine：

from math import radians,cos,sin,asin,sqrt
def haversine(lon1,lat1,lon2,lat2):
    #convert decimals to radians
    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 * asin(sqrt(a)) 
    r = 6371 # Radius of earth in kilometers. Use 3956 for miles
    return c * r

haversine(-97.481,-97.622,-74.1083,-74.106)

现在我想找到我的df中的点的距离，如果它们在纬度和长度的泽西城市半径50公里范围内：

import pandas as pd

df = pd.DataFrame({'Company':['WM','WS','WC','WW'],
                   'city':['Norman','OKC','NY','Bayonne'],
                   'latitude':[35.221,35.463,41.112,40.66],
                   'longtitude':[-97.481,-97.622,-74.1083,-74.106]})

jersey_city_lat_lon=(40.94,-74.05)
df['distance']=df.apply(haversine,args=(jersey_city_lat_lon),axis=1)
df[df['distance']<=100]

但是，当我运行上面的操作时，我收到一个错误：

Traceback (most recent call last):

  File "<ipython-input-123-8d33df9e0fab>", line 7, in <module>
    df['distance']=df.apply(haversine,args=(jersey_city_lat_lon),axis=1)

  File "C:\Users\j\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\frame.py", line 6487, in apply
    return op.get_result()

  File "C:\Users\j\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\apply.py", line 151, in get_result
    return self.apply_standard()

  File "C:\Users\j\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\apply.py", line 257, in apply_standard
    self.apply_series_generator()

  File "C:\Users\j\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\apply.py", line 286, in apply_series_generator
    results[i] = self.f(v)

  File "C:\Users\j\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\apply.py", line 78, in f
    return func(x, *args, **kwds)

TypeError: ("haversine() missing 1 required positional argument: 'lat2'", 'occurred at index 0')

它应该工作，并告诉我一个位置在纽约，另一个位于巴约讷，这是我们正在寻找的半径范围内，因为纽约和巴约讷都在距离泽西市50公里的径向距离内。 为什么我会收到此错误？

Answer 1

df.apply将行对象（或轴= 0的列）传递给目标函数。 它不知道将行解压缩到您想要的字段。 您可以将hasrsign函数包装为仅提取lat和lon列

jersey_city_long_lat=(-74.05,40.94)
def row_hsign(row):
    return haversine(*jersey_city_long_lat,row['longtitude'],row['latitude'])

df['distance']=df.apply(row_hsign,axis=1)