Question

我有一个包含四列中两个点的经/纬度的数据集，并尝试使用geopy.distance在新添加的列中计算它们之间的距离。

如果我仅计算一个值，但不适用于整个列，则效果很好。

import pandas as pd
from geopy import distance

sub_set = main[['Site_1','Site_Longitude_1','Site_Latitude_1','Site_2','Site_Longitude_2','Site_Latitude_2']]

lat1 = sub_set['Site_Latitude_1']
lat2 = sub_set['Site_Latitude_2']
long1 = sub_set['Site_Longitude_1']
long2 = sub_set['Site_Longitude_2']

数据帧sub_set如下

  Site_1 Site_Longitude_1 Site_Latitude_1 Site_2 Site_Longitude_2 Site_Latitude_2
0      A      -118.645167       34.237917     A2     -118.6499422     34.24973484
1      A      -118.645167       34.237917     A2     -118.6499422     34.24973484
2      B      -118.626659       34.224762     A2     -118.6499422     34.24973484
3      B      -118.626659       34.224762     A2     -118.6499422     34.24973484
4      B      -118.626659       34.224762     A2     -118.6499422     34.24973484

执行时，

sub_set['Distance'] = distance.distance((lat1,long1),(lat2,long2)).miles

抛出以下错误消息，

ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all()

Answer 1

以下内容将为您提供所需的按行计算。
不需要subset的东西
这是一条很长的线，但是它受益于所需列的绝对位置

df['Distance'] = df[['Site_Latitude_1', 'Site_Longitude_1', 'Site_Latitude_2', 'Site_Longitude_2']].apply(lambda x: distance.distance((x[0],x[1]), (x[2],x[3])).miles, axis=1)

更短的代码行

只需确保为x[]中的正确列正确索引了df

df['Distance'] = df.apply(lambda x: distance.distance((x[2],x[1]), (x[5],x[4])).miles, axis=1)

输出：

  Site_1 Site_Longitude_1 Site_Latitude_1 Site_2 Site_Longitude_2 Site_Latitude_2  Distance
0      A      -118.645167       34.237917     A2     -118.6499422     34.24973484  0.859202
1      A      -118.645167       34.237917     A2     -118.6499422     34.24973484  0.859202
2      B      -118.626659       34.224762     A2     -118.6499422     34.24973484  2.177003
3      B      -118.626659       34.224762     A2     -118.6499422     34.24973484  2.177003
4      B      -118.626659       34.224762     A2     -118.6499422     34.24973484  2.177003

Answer 2

我是新来的，但我想我可以帮忙。

问题是因为您正在使用序列来处理需要单个值的方法。您应该遍历行以单独选择每个值。

尝试以下代码：

this.store.pipe(
  select(currentAuthToken),
  take(1) // only if you need one time call rather than a call every time token is updated in ngrx
  switchMap(token => { // in this callback token will be string
    const httpHeaders = new HttpHeaders();

    httpHeaders.append('Authorization', 'Bearer ' + token);
    httpHeaders.append('Content-Type', 'application/json');
    return this.http.get<User>(API_USERS_URL, { headers: httpHeaders });
  })
).subscribe(user => console.log({user}));

输出：

    for row in sub_set.index:
      site1 =(sub_set.loc[row, 'Site_Latitude_1'],sub_set.loc[row, 'Site_Longitude_1'])
      site2 =(sub_set.loc[row, 'Site_Latitude_2'],sub_set.loc[row, 'Site_Longitude_2'])
      print('Distance is:',(distance.distance(site1, site2).miles),'miles')

或：

Distance is: 0.8592022243334677 miles
Distance is: 0.8592022243334677 miles
Distance is: 2.1770033222544773 miles
Distance is: 2.1770033222544773 miles
Distance is: 2.1770033222544773 miles

输出：

dist =[] 
for row in sub_set.index:
  site1 =(sub_set.loc[row, 'Site_Latitude_1'],sub_set.loc[row, 
  'Site_Longitude_1'])
  site2 =(sub_set.loc[row, 'Site_Latitude_2'],sub_set.loc[row, 
  'Site_Longitude_2'])
  dist.append((distance.distance(site1, site2).miles))
sub_set['Distance'] = dist

计算熊猫数据框中的距离给出错误

2 个答案:

更短的代码行

输出：