python - 在 csv 文件中查找每个月的最高温度？

Question

我需要一些帮助。所以我有一个 large csv file (+8785 行)。

所以，我基本上需要的是获取每个月的最高温度。例如(输出):

Month Max Temperature

January 5.3
February 6.1
March 25.5
...

我是这样写的:

temp = open("weather_2012.csv","r")
total = 0
maxt = 0.0

for line in temp:
    try:
        p = float(line.split(",")[1])
        total += 1
        maxt = max(maxt,p)
    except:
        pass

print("Maximum:",maxt)

但它只获得了整个月(总体)的一个最高温度:

Maximum: 33.0

Answer 1

这是我认为的好方法，因为它避免了将许多(如果不是大多数)值硬编码到所需的代码中(因此适用于任何年份，并使用特定于区域设置的月份名称):

from calendar import month_name
import csv
from datetime import datetime
import sys

filename = 'weather_2012.csv'
max_temps = [-sys.maxsize] * 13  # has extra [0] entry

with open(filename, 'r', newline='') as csvfile:
    reader = csv.reader(csvfile); next(reader)  # skip header row
    for date, high_temp, *_ in reader:
        month = datetime.strptime(date, '%Y-%m-%d %H:%M:%S').month
        max_temps[month] = max(max_temps[month], float(high_temp))

print('Monthly Max Temperatures\n')
longest = max(len(month) for month in month_name)  # length of longest month name
for month, temp in enumerate(max_temps[1:], 1):
    print('{:>{width}}: {:5.1f}'.format(month_name[month], temp, width=longest))

输出:

Monthly Max Temperatures

  January:   5.3
 February:   6.1
    March:  25.5
    April:  27.8
      May:  31.2
     June:  33.0
     July:  33.0
   August:  32.8
September:  28.4
  October:  21.1
 November:  17.5
 December:  11.9