按月过滤 CSV 并使用该月数据创建新的 csv

Question

每当“呼叫解决时间”列中出现新月份时，我都希望使用该月份和年份创建一个新的 csv 文件。并将包含该月份和年份的所有行过滤到该新 csv 中。

像这样：

alldata.csv

Call Resolve Time   Priority    Overall Result
8/6/2015                  P4    F
5/13/2015                 P4    F
4/28/2015                 P4    P
5/13/2015                 P4    F
5/27/2015                 P4    F

从 alldata.csv 创建的新文件 May-2015.csv 仅包含 2015 年 5 月 XX 日的数据

Call Resolve Time   Priority    Overall Result
    5/13/2015                 P4    F
    5/13/2015                 P4    F
    5/27/2015                 P4    F

到目前为止，我有这个，但我必须手动为每年和每月创建一些东西：

reader = csv.reader(open(r"alldata.csv"), delimiter=',') 
filtered = filter(lambda p: '5/27/15' == p[1], reader) 
csv.writer(open(r"May-2015.csv",'w'),delimiter=',').writerows(filtered)

编辑 ---------------------------------------------- -----------------------------

# say, reader is the reader object
# do next(reader) to skip the headings
import csv
from itertools import groupby

reader = csv.reader(open(r"alldata.csv"), delimiter=',')

def by_month (row):
    date = row[7] 
    month = int(date.split("/", 1)[0])
    return month

m_g = groupby(reader, by_month)

for month, group in m_g:
    group = list(group)
    # use a month to month_name map
    with open('{}.csv'.format(month), 'w') as fw:
        w = csv.writer(fw)
        w.writerows(group)

手动添加日期：

def by_month(row):
    date = '5/9/2016'
    month = int(date.split("/", 1)[0])
    return month

Answer 1

试试下面的，

# say, reader is the reader object
# do next(reader) to skip the headings
from itertools import groupby
def by_month(row):
    date = row[0] 
    month = int(date.split("/", 1)[0])
    return month

m_g = groupby(reader, by_month)

for month, group in m_g:
    group = list(group)
    # use a month to month_name map
    with open('{}.csv'.format(month), 'w') as fw:
        w = csv.writer(fw)
        w.writerows(group)

评论如果有什么不工作。