Python 包含str和int的.txt文件的平均值

我正在创建一个函数，用于读取包含以下内容的

.txt

文件：

Testing.txt：

a 1 34
b 2 25
c 3 23
j 4 80

我需要创建一个函数来读取此文件并打印文件中每行最后2位的平均值

到目前为止，我得到的是：

def Stats():

    filename = input("Enter a file name: ")
    with open(filename) as f:
        data = [int(line) for line in f]

    print("The average value is ", sum(data)/len(data))


Stats()

优点：

• 此函数将生成函数中int值的平均值

缺点：

• 如果文件中包含str，它将不起作用

---

问题：如何让我的函数与上面列出的文件（testing.txt）一起工作？

我想这就是您想要的：

# filename = input("Enter a file name: ")
filename = "input.txt"

def avg_file(filename):

    with open(filename, 'r') as f:
        data = [int(line.split()[2]) for line in f]
        return sum(data)/len(data)


avg =  avg_file(filename)

print("The average value is: ", avg)
# The average value is:  40.5

---

关键是这个

line.split（）[2]

。这将基于空格分割一条线，并取第三个值。

我想这就是您想要的：

# filename = input("Enter a file name: ")
filename = "input.txt"

def avg_file(filename):

    with open(filename, 'r') as f:
        data = [int(line.split()[2]) for line in f]
        return sum(data)/len(data)


avg =  avg_file(filename)

print("The average value is: ", avg)
# The average value is:  40.5

---

关键是这个

line.split（）[2]

。这将基于空格拆分一行，并取第三个值。

您可以通过这种方式忽略非数字：

data = [int(token) for token in f.read().split() if token.isdigit()]

---

您可以通过以下方式忽略非数字：

data = [int(token) for token in f.read().split() if token.isdigit()]

---

比如说：

import csv

def mean(lst): return sum(lst) / len(lst)

with open('input.txt') as f:
    reader = csv.reader(f, delimiter=' ')
    lines = [line for line in reader]

col3 = [int(line[2]) for line in lines]

print(mean(col3))  # 40.5

def mean(lst): return sum(lst) / float(len(lst))

with open('input.txt') as f:
    lines = [line.split() for line in f]

col3 = [int(line[2]) for line in lines]

print mean(col3)  # 40.5

这只是使用csv模块将文件行解析为包含元素的行。您可以通过以下方式完成相同的任务：

import csv

def mean(lst): return sum(lst) / len(lst)

with open('input.txt') as f:
    reader = csv.reader(f, delimiter=' ')
    lines = [line for line in reader]

col3 = [int(line[2]) for line in lines]

print(mean(col3))  # 40.5

def mean(lst): return sum(lst) / float(len(lst))

with open('input.txt') as f:
    lines = [line.split() for line in f]

col3 = [int(line[2]) for line in lines]

print mean(col3)  # 40.5

---

比如说：

import csv

def mean(lst): return sum(lst) / len(lst)

with open('input.txt') as f:
    reader = csv.reader(f, delimiter=' ')
    lines = [line for line in reader]

col3 = [int(line[2]) for line in lines]

print(mean(col3))  # 40.5

def mean(lst): return sum(lst) / float(len(lst))

with open('input.txt') as f:
    lines = [line.split() for line in f]

col3 = [int(line[2]) for line in lines]

print mean(col3)  # 40.5

这只是使用csv模块将文件行解析为包含元素的行。您可以通过以下方式完成相同的任务：

import csv

def mean(lst): return sum(lst) / len(lst)

with open('input.txt') as f:
    reader = csv.reader(f, delimiter=' ')
    lines = [line for line in reader]

col3 = [int(line[2]) for line in lines]

print(mean(col3))  # 40.5

def mean(lst): return sum(lst) / float(len(lst))

with open('input.txt') as f:
    lines = [line.split() for line in f]

col3 = [int(line[2]) for line in lines]

print mean(col3)  # 40.5

大概是这样的：

data = [sum(map(int, line.split(' ')[1:])) / 2 for line in f]

或者更老派的东西，以防字符串和int值的未知组合：

data = []
for line in f:
    integers = []
    for segment in line.split():
        try:
            integers.append(int(segment))
        except ValueError:
            pass
    data.append(sum(integers) / len(integers))

大概是这样的：

data = [sum(map(int, line.split(' ')[1:])) / 2 for line in f]

或者更老派的东西，以防字符串和int值的未知组合：

data = []
for line in f:
    integers = []
    for segment in line.split():
        try:
            integers.append(int(segment))
        except ValueError:
            pass
    data.append(sum(integers) / len(integers))