2017-09-02 21 views
0

嘗試將數據解析到列表的列表時遇到了問題。 我試圖抓取關於部門及其主題的信息。 但是,由於每個部門都有不同數量的主題,因此我需要創建一個列表清單,以便稍後將數據鏈接在一起。我已設法導航索引錯誤,並且問題似乎來自編譯主題列表。將數據解析到列表的列表

from lxml import html 
import requests 

page = requests.get('URL') 

page_source_code = html.fromstring(page.text) 


departments_list = [] 
subject_list = [] 

for dep in range(1,3): 
    departments = page_source_code.xpath('tag' 
             +str(dep)+']tag/text()') 

    ### print(dep, departments) 
    if departments == []: 
     pass 
    else: 
     departments_list.append(departments[0]) 


    for sub in range(1,20): 
     subjects = page_source_code.xpath('tag' 
             +str(dep)+']tag' 
             +str(sub)+']tag/text()') 
     ### print(sub, subjects) 
     if subjects == []: 
      pass 
     else: 
      subject_list.append(subjects[0]) 

print('Department list ------ ', len(departments_list), departments_list, '\n') 
print('Subject list ------ ', len(subject_list), subject_list) 

我的輸出是這樣的:

Department list ------ 2 ['Department_1', 'Department_2'] 

Subject list ------ 7 ['Subject_1'(dep_1), 'Subject_2 '(dep_1), 'Subject_3 '(dep_1), 'Subject_4'(dep_1), 'Subject_5'(dep_2), 'Subject_6 '(dep_2), 'Subject_7 '(dep_2)'] 

此代碼似乎把所有科目到一個列表。我想,如下所示:

Subject list ------ 7 [['Subject_1'(dep_1), 'Subject_2 '(dep_1), 'Subject_3 '(dep_1), 'Subject_4'(dep_1)], ['Subject_5'(dep_2), 'Subject_6 '(dep_2), 'Subject_7 '(dep_2)']] 

回答

0

需要兩個全局添加兩個列表主題列表中 ,找出受試者[0]字符串「dep_1」或「dep_2」字。

 #declare the list for subject 
    sub_list1 = [] sub_list2 = [] 

    #this code is under the second for loop 
    if subjects.find('dep_1') == -1 : 
     sub_list2.append(subjects[0]) 
    else: 
     sub_list1.append(subjects[0]) 

    #Please remove the subjectList.append statement 
    #from second for loop 
    #and put it end of both loop like that . 
    subjectList = [sub_list1,sub_list2]