Question

我正在尝试在python 27中读取csv文件来创建字典。 CSV文件看起来像 -

SI1440269，SI1320943，SI1321085   SI1440270，SI1320943，SI1321085，SI1320739   SI1440271，SI1320943
  SI1440273，SI1321058，SI1320943，SI1320943

每行中的条目数不固定。第一列条目应该是我的密钥。我的代码 -

SELECT 
    CASE
       WHEN a >= b AND a >= c THEN a 
       WHEN b >= a AND b >= c THEN b 
       ELSE c  
    END AS a,
    CASE
       WHEN b >= c AND a >= b THEN b 
       WHEN b >= a AND c >= b THEN b 
       WHEN c >= a AND b >= c THEN c 
       WHEN c >= b AND a >= c THEN c 
       ELSE a 
    END AS b, 
    CASE 
       WHEN b >= c AND a >= c THEN c 
       WHEN a <= c AND a <= b THEN a 
       ELSE b 
    END AS c

输出：

{＆＃39; SI1440273＆＃39;：[＆＃39; SI1321058＆＃39;，＆＃39; SI1320943＆＃39;，＆＃39; SI1320943＆＃39;]，＆＃39;＆＃39; ：[＆＃39;＆＃39;＆＃39;＆＃39;，＆＃39;＆＃39;]，＆＃39; SI1440271＆＃39;：[＆＃39; SI1320943＆＃39;，＆＃39;＆＃39;，＆＃39;＆＃39;]，＆＃39; SI1440270＆＃39;：[＆＃39; SI1320943＆＃39;，＆＃39; SI1321085＆＃39;，＆＃39; SI1320739＆＃39;]，＆＃39; SI1440269＆＃39;：[＆＃39; SI1320943＆＃39;，＆＃39; SI1321085＆＃39;，＆＃39;＆＃39;]}

如何摆脱输出中的空值？另外，如何让输出中的键值与csv文件中的键值相同？

编辑：我想要单行按键＆＃39;

Answer 1

您可以使用csv.DictReader，如下所示：

import csv

result = {}
with open('test.csv') as csvfile:
    reader = csv.DictReader(csvfile, delimiter=" ", fieldnames=["id"], restkey="data")
    for row in reader:
        print row
        result[row["id"]] = row["data"]

print result

这将为您提供每行字典解决方案，因此您可以一次处理一行。然后我还将它们全部附加到一个result字典中。

从这里你将得到以下输出：

{'data': ['SI1320943', 'SI1321085'], 'id': 'SI1440269'}
{'data': ['SI1320943', 'SI1321085', 'SI1320739', 'SI1440271', 'SI1320943'], 'id': 'SI1440270'}
{'data': ['SI1321058', 'SI1320943', 'SI1320943'], 'id': 'SI1440273'}
{'SI1440273': ['SI1321058', 'SI1320943', 'SI1320943'], 'SI1440270': ['SI1320943', 'SI1321085', 'SI1320739', 'SI1440271', 'SI1320943'], 'SI1440269': ['SI1320943', 'SI1321085']}

Answer 2

试试这个

import csv
reader = csv.reader(open('test.csv'))

result = {row[0]:row[1:] for row in reader if row and row[0]}
print result

如果你想进一步消除值中的null，那么请按照

进行操作

import csv
reader = csv.reader(open('test.csv'))

result = {row[0]:[i for i in row[1:] if i] for row in reader if row and row[0]}
print result

保留录取顺序

from collections import OrderedDict
result = OrderedDict()
for row in reader:
   if row and row[0]:
      result[row[0]]=[i for i in row[1:] if i]

# print result
for key in result:
   print key,":" ,result[key]

Answer 3

如前所述，这不是CSV - 所以readline和split更合适，并使用OrderedDict来保持输入顺序：

import csv
from collections import OrderedDict
result = OrderedDict()
with open('test.csv') as f:
    for row  in f:
        row=row.strip().split()
        key = row[0]
        result[key] = row[1:]
print result

在Python中读取csv文件并创建一个字典

3 个答案: