我有一个大约有2000条记录的CSV文件。
每条记录都有一个字符串和一个类别:
This is the first line,Line1
This is the second line,Line2
This is the third line,Line3
我需要把这个文件读入一个列表，看起来像这样:
data = [('This is the first line', 'Line1'),
('This is the second line', 'Line2'),
('This is the third line', 'Line3')]
如何使用Python将此CSV导入到我需要的列表?
当前回答
使用csv模块:
import csv
with open('file.csv', newline='') as f:
reader = csv.reader(f)
data = list(reader)
print(data)
输出:
[['This is the first line', 'Line1'], ['This is the second line', 'Line2'], ['This is the third line', 'Line3']]
如果你需要元组:
import csv
with open('file.csv', newline='') as f:
reader = csv.reader(f)
data = [tuple(row) for row in reader]
print(data)
输出:
[('This is the first line', 'Line1'), ('This is the second line', 'Line2'), ('This is the third line', 'Line3')]
旧的Python 2答案，同样使用csv模块:
import csv
with open('file.csv', 'rb') as f:
reader = csv.reader(f)
your_list = list(reader)
print your_list
# [['This is the first line', 'Line1'],
# ['This is the second line', 'Line2'],
# ['This is the third line', 'Line3']]
其他回答
针对Python 3更新:
import csv
with open('file.csv', newline='') as f:
reader = csv.reader(f)
your_list = list(reader)
print(your_list)
输出:
[['This is the first line', 'Line1'], ['This is the second line', 'Line2'], ['This is the third line', 'Line3']]
如果确定输入中没有逗号，而不是分隔类别，则可以逐行读取文件并在，，上进行分割，然后将结果推入List
也就是说，看起来您正在查看一个CSV文件，因此您可以考虑为它使用模块
扩展一下您的需求，假设您不关心行顺序，并希望将它们分组到类别下，下面的解决方案可能适合您:
>>> fname = "lines.txt"
>>> from collections import defaultdict
>>> dct = defaultdict(list)
>>> with open(fname) as f:
... for line in f:
... text, cat = line.rstrip("\n").split(",", 1)
... dct[cat].append(text)
...
>>> dct
defaultdict(<type 'list'>, {' CatA': ['This is the first line', 'This is the another line'], ' CatC': ['This is the third line'], ' CatB': ['This is the second line', 'This is the last line']})
通过这种方式，您可以在类别的键下获得字典中所有可用的相关行。
接下来是一段代码，它使用csv模块，但使用第一行(csv表的头)将file.csv内容提取到dicts列表
import csv
def csv2dicts(filename):
with open(filename, 'rb') as f:
reader = csv.reader(f)
lines = list(reader)
if len(lines) < 2: return None
names = lines[0]
if len(names) < 1: return None
dicts = []
for values in lines[1:]:
if len(values) != len(names): return None
d = {}
for i,_ in enumerate(names):
d[names[i]] = values[i]
dicts.append(d)
return dicts
return None
if __name__ == '__main__':
your_list = csv2dicts('file.csv')
print your_list
result = []
for line in text.splitlines():
result.append(tuple(line.split(",")))
