Question

我无法弄清楚python pandas中是否有语句。

我有一个数据帧df

Category | Count
A           45756
B           5857
C           57876

我创建一个列表，然后将其用作层次结构

list_s = {'A':'Y',
'B':'Y'}
df['Flag'] = df['Category'].replace(list_s)

但我得到

Category | Count   | Flag 
A           45756     Y
B           5857      Y
C           57876     C

而不是

Category | Count   | Flag 
A           45756     Y
B           5857      Y
C           57876

谢谢！

Answer 1

将lambda与get函数一起使用，您可以使用字典list_s = {'A':'Y', 'B':'Y'} df['Flag'] = df['Category'].map(lambda x: list_s.get(x, '')) print(df) Category Count Flag 0 A 45756 Y 1 B 5857 Y 2 C 57876方法传递默认值

@Controller
public class ApplicantApplicationsListController extends ApplicantController {


    /**
     * @throws Exception    
     *                                 
     */
    @RequestMapping(value = {       "/medrano/applicant/home",                                   
                                    "/medrano/applicant/home/"}, method = {RequestMethod.GET})
    public String viewProductApplications   (@ModelAttribute("applicationApplicationsListForm") final ApplicationApplicationsListForm applicationApplicationsListForm,
                                             HttpServletRequest request,
                                             Model model ) throws Exception {

        return "applicantApplicationsView";

    }

Answer 2

IIUC你可以这样做：

In [8]: df['Flag'] = df['Category'].map(list_s).fillna('')

In [9]: df
Out[9]:
  Category  Count Flag
0        A  45756    Y
1        B   5857    Y
2        C  57876

python Pandas如果列表中的单词在新列

2 个答案: