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
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。
其他回答
这是Python 3中最简单的方法。x导入CSV到多维数组，它只有4行代码，没有导入任何东西!
#pull a CSV into a multidimensional array in 4 lines!
L=[] #Create an empty list for the main array
for line in open('log.txt'): #Open the file and read all the lines
x=line.rstrip() #Strip the \n from each line
L.append(x.split(',')) #Split each line into a list and add it to the
#Multidimensional array
print(L)
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
正如在评论中已经说过的，你可以在python中使用csv库。CSV意味着用逗号分隔的值，这似乎正是您的情况:一个标签和一个用逗号分隔的值。
作为一个类别和值类型，我宁愿使用字典类型而不是元组列表。
无论如何，在下面的代码中我展示了两种方式:d是字典，l是元组列表。
import csv
file_name = "test.txt"
try:
csvfile = open(file_name, 'rt')
except:
print("File not found")
csvReader = csv.reader(csvfile, delimiter=",")
d = dict()
l = list()
for row in csvReader:
d[row[1]] = row[0]
l.append((row[0], row[1]))
print(d)
print(l)
一个简单的循环就足够了:
lines = []
with open('test.txt', 'r') as f:
for line in f.readlines():
l,name = line.strip().split(',')
lines.append((l,name))
print lines
