我想计算一个字母数字的总和

Question

这是原始列表：

ticket_list=

["AI567:MUM:LON:014",

"AI077:MUM:LON:056",

"BA896:MUM:LON:067",

"SI267:MUM:SIN:145",

"AI077:MUM:CAN:060",

"SI267:BLR:MUM:148",

"AI567:CHE:SIN:015",

"AI077:MUM:SIN:050",

"AI077:MUM:LON:051",

"SI267:MUM:SIN:146"]

我试图从中生成一个子列表，如下所示：

['AI077:077', 'AI077:077', 'AI077:077', 'AI077:077', 'AI567:567', 'AI567:567', 'BA896:896', 'SI267:267', 'SI267:267', 'SI267:267']

我已经成功地生成了列表，现在我正试图根据**“：”之后的值来计算排序后的列表**的总和

预期输出：

[AI077:308, AI567:1134, BA896:896, SI267:801]

我的代码：

def find_passengers_per_flight():
    flight_name=[]
    flight_passenger=[]
   """
    In the list, details should be provided in the format:
    [flight_no:no_of_passengers, flight_no:no_of_passengers, etc.]."""


    for t in ticket_list:
        res=''
        res = re.search(r"[A-Z]*\d*|[a-z]*\d*",t).group()

        flight_name.append(res)

    for i in flight_name:

        new_str=''
        res2 = re.search(r"\d+",i).group()
        new_str+=':'+res2
        flight_passenger.append(i+new_str)


    print(sorted(flight_passenger))

我的输出：

['AI077:077', 'AI077:077', 'AI077:077', 'AI077:077', 'AI567:567', 'AI567:567', 'BA896:896', 'SI267:267', 'SI267:267', 'SI267:267']

Answer 1

使用defaultdict会更容易，如果您坚持让输出作为一个列表，请稍后转换：

from collections import defaultdict

l = ['AI077:077', 'AI077:077', 'AI077:077', 'AI077:077', 'AI567:567', 'AI567:567', 'BA896:896', 'SI267:267', 'SI267:267', 'SI267:267']
d = defaultdict(int)

for e in l:
    name, number = e.split(':')
    number = int(number)
    d[name] += number

print(d)
#  defaultdict(<class 'int'>, {'AI077': 308, 'AI567': 1134, 'BA896': 896, 'SI267': 801})
print(['{}:{}'.format(k, v) for k, v in d.items()])
#  ['AI077:308', 'AI567:1134', 'BA896:896', 'SI267:801']

如果您使用的是Python<；=3.6，则不能保证输出的顺序总是相同的，我认为这无关紧要。你知道吗

Answer 2

如果你真的想汇总航班号，你可以直接从原始数据中创建元组，并将它们汇总成dict：（使用defaultdict更好）

t = ['AI077:077', 'AI077:077', 'AI077:077', 'AI077:077', 'AI567:567',
     'AI567:567', 'BA896:896', 'SI267:267', 'SI267:267', 'SI267:267']

trimmed = [(y[0:5],int(y[6:])) for y in t]

summs = {}
for flight,price in trimmed:
    summs.setdefault(flight,0)
    summs[flight] += price

print(summs) 

输出：

{'BA896': 896, 'SI267': 801, 'AI077': 308, 'AI567': 1134}

---

不过，我觉得有点奇怪的是，你似乎用了航班名称中的航班号来计算乘客人数——你不应该计算每个航班售出的机票吗？

---

点票：

               #flight : from : to : seat-number
ticket_list= ["AI567:MUM:LON:014", "AI077:MUM:LON:056", "BA896:MUM:LON:067",
              "SI267:MUM:SIN:145", "AI077:MUM:CAN:060", "SI267:BLR:MUM:148", 
              "AI567:CHE:SIN:015", "AI077:MUM:SIN:050", "AI077:MUM:LON:051",
              "SI267:MUM:SIN:146"]

from collections import Counter
c = Counter ((t.split(":")[0] for t in ticket_list))

print(c)

输出：

# sold tickets per flight
Counter({'AI077': 4, 'SI267': 3, 'AI567': 2, 'BA896': 1})

---

您还可以使用排序列表中的groupby from itertools对您的航班进行分组，并对其进行评估，如下所示：

from itertools import groupby

# if you need the tickets as well:
grp = groupby(sorted(ticket_list), lambda x:x[:6])

for g in grp:
    key, seats = g
    seats = list(seats)
    print(f"Flight: {key} has sold seats {len(seats)}: {','.join( x.split(':')[-1] for x in seats)}")

Flight: AI077: has sold seats 4: 060,051,056,050
Flight: AI567: has sold seats 2: 015,014
Flight: BA896: has sold seats 1: 067
Flight: SI267: has sold seats 3: 148,145,146

Answer 3

看起来好像你在把航班号加在一起，但是我想你应该把乘客总数加在一起，就像这样：

import re

tickets = {}
for i in ticket_list:
    data = re.findall(r'(^[A-Z]+[0-9]+).*?([0-9]+$)', i)[0]
    if data[0] in tickets.keys():
        tickets[data[0]] += int(data[1])
    else:
        tickets[data[0]] = int(data[1])

因此tickets返回：

{'AI567': 29, 'AI077': 217, 'BA896': 67, 'SI267': 439}