Python比較兩個csv文件並將數據附加到csv文件

Question

我有以下格式的兩個csv文件：

第一個是outputTweetsDate.csv：

Here is some text;13.09.13 16:45
Here is more text;13.09.13 16:45
And yet another text;13.09.13 16:46

第二個文件是apiSheet.csv：

13.09.13 16:46;89.56
13.09.13 16:45;90.40

我想比較這兩個文件，如果兩個日期時間值匹配，則將文本和數據添加到一個新文件（finalOutput.csv）中：

|89.56|,|Here is some text|
|89.56|,|Here is more text|
|90.49|,|And yet another text|

這是我到目前為止的代碼：

with open("apiSheet.csv", "U") as in_file1, open("outputTweetsDate.csv", "rb") as in_file2,open("finalOutput.csv", "wb") as out_file:
   reader1 = csv.reader(in_file1,delimiter=';')
   reader2 = csv.reader(in_file2,delimiter='|')
   writer = csv.writer(out_file,delimiter='|')
   for row1 in reader1:
       for row2 in reader2:
           if row1[0] == row2[1]:
               data = [row1[1],row2[0]]
               print data
               writer.writerow(data)

我編輯了代碼，到目前為止，它可以正常工作，但是它不能正確遍歷所有代碼。 暫時我的輸出是這樣的：

|89.56|,|Here is some text|
|89.56|,|Here is more text|

因此，即使它們相同，也不會向我顯示第三個。 似乎沒有遍歷文件。

謝謝！

Answer 1

在讀取文件1的第二行之前，第二個循環到達文件2的末尾（outputTweetsDate.csv）。

試試這個片段：

 with open("apiSheet.csv", "U") as in_file1, open("outputTweetsDate.csv", "rb") as in_file2,open("finalOutput.csv", "wb") as out_file:
   reader1 = csv.reader(in_file1,delimiter=';')
   reader2 = csv.reader(in_file2,delimiter='|')
   writer = csv.writer(out_file,delimiter='|')
   row2 = reader2.next()
   for row1 in reader1:
       while row2 and row1[0] <= row2[1]:
           if row1[0] == row2[1]:
               data = [row1[1],row2[0]]
               print data
               writer.writerow(data)
           row2 = reader2.next()

編輯逆序比較棘手。 讓我們停止嘗試變得聰明，做些蠻力。 由於文件遠遠少於您的RAM，它將可以完美地工作。

 with open("apiSheet.csv", "U") as in_file1, open("outputTweetsDate.csv", "rb") as in_file2,open("finalOutput.csv", "wb") as out_file:
   reader1 = csv.reader(in_file1,delimiter=';')
   reader2 = csv.reader(in_file2,delimiter='|')
   writer = csv.writer(out_file,delimiter='|')

   rows2 = [row for row in reader2] # all the content of file2 goes in RAM.
   for row1 in reader1:
       for row2 in rows2:
           if row1[0] == row2[1]:
               data = [row1[1],row2[0]]
               print data
               writer.writerow(data)