python - 如何使用 CSV 文件的唯一值在 Python 中创建列表？

Question

我有如下所示的 CSV 文件，

1994, Category1, Something Happened 1
1994, Category2, Something Happened 2
1995, Category1, Something Happened 3
1996, Category3, Something Happened 4
1998, Category2, Something Happened 5

我想创建两个列表，

Category = [Category1, Category2, Category3]

和

Year = [1994, 1995, 1996, 1998]

我想省略列中的重复项。我正在阅读文件如下，

DataCaptured = csv.reader(DataFile, delimiter=',')  
DataCaptured.next()

和循环，

   for Column in DataCaptured:

Answer 1

你可以这样做:

DataCaptured = csv.reader(DataFile, delimiter=',', skipinitialspace=True) 

Category, Year = [], []
for row in DataCaptured:
    if row[0] not in Year:
        Year.append(row[0])
    if row[1] not in Category:
        Category.append(row[1])    

print Category, Year        
# ['Category1', 'Category2', 'Category3'] ['1994', '1995', '1996', '1998']

---

如评论中所述，如果顺序无关紧要，使用集合会更容易和更快:

Category, Year = set(), set()
for row in DataCaptured:
    Year.add(row[0])
    Category.add(row[1])