Python 特定数字和四舍五入数字之和，小数点后两位

我试图在不改变文件本身的情况下从文件中获取某些数字的总和

1 #person number
Marlon Holmes  #Name
18.86 # First number
13.02 # Second Number
13.36 # Third Number

对于数字之和，它必须是第一、第二和第三个数字

当前的数字以厘米为单位，已转换为英寸，小数点后两位是必要的

我目前的代码是根据第一、第二和第三个数字的总和提供前三名

当前代码：

data = []
names = OrderedDict([('Competitor Number', int),
    ('Competitor Name', str),
    ('Cucumber', to_inch),
    ('Carrot', to_inch),
    ('Runner Bean', to_inch)])

with open('veggies_2016.txt') as fobj:
    while True:
        item = {}
        try:
            for name, func in names.items():
                item[name] = func(next(fobj).strip())
            data.append(item)
        except StopIteration:
            break
sorted_data = sorted(data, key=itemgetter('Runner Bean'), reverse = True)
for entry in sorted_data[:3]:
    for key, value in entry.items():
        print value
    print

在我读取的文件中大约有50条记录，必须将所有记录的总和相加，然后放入，以便找到前3位，最好是小数点后两位

表示_英寸的代码：

def to_inch(cm):
    return float(cm) / 2.54

整个文档围绕主菜单工作

---

为了得到总和，我尝试了

sum（item.entry.items（））

，但没有成功，也尝试了

“%.2f”

十进制数字/有效数字，但没有成功，如果我们现在不考虑从文件中读取数据，并且假设我们可以将数字放入

列表中，我们可以使用Python的，那么任何帮助都将不胜感激

代码：

numbers = [18.86, 13.02, 13.36]

def to_inch(cm):
    return cm/2.54

numbers_in_inches = list(map(to_inch, numbers))
print(numbers_in_inches)

numbers_rounded = list(map(round, numbers_in_inches, [0 for _ in numbers]))
print(numbers_rounded)

sum_numbers = sum(numbers_rounded)
print(sum_numbers)

[7.4251968503937, 5.125984251968504, 5.259842519685039]
[7.0, 5.0, 5.0]
17.0

import re

numbers_names = {}
numbers = []
player_number = ''
name = ''

with open('file.txt', 'r') as f:
    for line in f:
        if '#person number' in line:
            player_number = int(line.split('#')[0])
        elif '#Name' in line:
            name = line.split('#')[0]
        else:
            line_numbers = re.sub(r"[^\d.]", "", line)
            if '.' in line_numbers:
                numbers.append(float(line_numbers))
        if len(numbers) >= 3 and player_number and name:
            numbers_names.update({'player_number': player_number, 'name': name,  'numbers': numbers})
            numbers, player_number, name = [], 0, ''

print(numbers_names)

{'name': 'Marlon Holmes  ', 'numbers': [18.86, 13.02, 13.36], 'player_number': 1}

输出：

numbers = [18.86, 13.02, 13.36]

def to_inch(cm):
    return cm/2.54

numbers_in_inches = list(map(to_inch, numbers))
print(numbers_in_inches)

numbers_rounded = list(map(round, numbers_in_inches, [0 for _ in numbers]))
print(numbers_rounded)

sum_numbers = sum(numbers_rounded)
print(sum_numbers)

[7.4251968503937, 5.125984251968504, 5.259842519685039]
[7.0, 5.0, 5.0]
17.0

import re

numbers_names = {}
numbers = []
player_number = ''
name = ''

with open('file.txt', 'r') as f:
    for line in f:
        if '#person number' in line:
            player_number = int(line.split('#')[0])
        elif '#Name' in line:
            name = line.split('#')[0]
        else:
            line_numbers = re.sub(r"[^\d.]", "", line)
            if '.' in line_numbers:
                numbers.append(float(line_numbers))
        if len(numbers) >= 3 and player_number and name:
            numbers_names.update({'player_number': player_number, 'name': name,  'numbers': numbers})
            numbers, player_number, name = [], 0, ''

print(numbers_names)

{'name': 'Marlon Holmes  ', 'numbers': [18.86, 13.02, 13.36], 'player_number': 1}

发生了什么：

numbers = [18.86, 13.02, 13.36]

def to_inch(cm):
    return cm/2.54

numbers_in_inches = list(map(to_inch, numbers))
print(numbers_in_inches)

numbers_rounded = list(map(round, numbers_in_inches, [0 for _ in numbers]))
print(numbers_rounded)

sum_numbers = sum(numbers_rounded)
print(sum_numbers)

[7.4251968503937, 5.125984251968504, 5.259842519685039]
[7.0, 5.0, 5.0]
17.0

import re

numbers_names = {}
numbers = []
player_number = ''
name = ''

with open('file.txt', 'r') as f:
    for line in f:
        if '#person number' in line:
            player_number = int(line.split('#')[0])
        elif '#Name' in line:
            name = line.split('#')[0]
        else:
            line_numbers = re.sub(r"[^\d.]", "", line)
            if '.' in line_numbers:
                numbers.append(float(line_numbers))
        if len(numbers) >= 3 and player_number and name:
            numbers_names.update({'player_number': player_number, 'name': name,  'numbers': numbers})
            numbers, player_number, name = [], 0, ''

print(numbers_names)

{'name': 'Marlon Holmes  ', 'numbers': [18.86, 13.02, 13.36], 'player_number': 1}

将您的功能
映射到列表中每个项目的\u inch
将Python的
round（）
函数映射到
numbers\u in.
中的每个值上，最后理解列表的理由是它为
map（）
创建了一个
0
的列表，用于
round（number，places）
的
位置

使用Python的
sum（）
对所有数字求和，当然，如果要在求和后进行取整，可以使用
round（sum\u numbers，0）
。注意：如果您想在求和之后对进行取整，请使用
math.fsum
而不是科波菲尔在评论中提到的
sum

现在分析文件：

numbers = [18.86, 13.02, 13.36]

def to_inch(cm):
    return cm/2.54

numbers_in_inches = list(map(to_inch, numbers))
print(numbers_in_inches)

numbers_rounded = list(map(round, numbers_in_inches, [0 for _ in numbers]))
print(numbers_rounded)

sum_numbers = sum(numbers_rounded)
print(sum_numbers)

[7.4251968503937, 5.125984251968504, 5.259842519685039]
[7.0, 5.0, 5.0]
17.0

import re

numbers_names = {}
numbers = []
player_number = ''
name = ''

with open('file.txt', 'r') as f:
    for line in f:
        if '#person number' in line:
            player_number = int(line.split('#')[0])
        elif '#Name' in line:
            name = line.split('#')[0]
        else:
            line_numbers = re.sub(r"[^\d.]", "", line)
            if '.' in line_numbers:
                numbers.append(float(line_numbers))
        if len(numbers) >= 3 and player_number and name:
            numbers_names.update({'player_number': player_number, 'name': name,  'numbers': numbers})
            numbers, player_number, name = [], 0, ''

print(numbers_names)

{'name': 'Marlon Holmes  ', 'numbers': [18.86, 13.02, 13.36], 'player_number': 1}

输出：

numbers = [18.86, 13.02, 13.36]

def to_inch(cm):
    return cm/2.54

numbers_in_inches = list(map(to_inch, numbers))
print(numbers_in_inches)

numbers_rounded = list(map(round, numbers_in_inches, [0 for _ in numbers]))
print(numbers_rounded)

sum_numbers = sum(numbers_rounded)
print(sum_numbers)

[7.4251968503937, 5.125984251968504, 5.259842519685039]
[7.0, 5.0, 5.0]
17.0

import re

numbers_names = {}
numbers = []
player_number = ''
name = ''

with open('file.txt', 'r') as f:
    for line in f:
        if '#person number' in line:
            player_number = int(line.split('#')[0])
        elif '#Name' in line:
            name = line.split('#')[0]
        else:
            line_numbers = re.sub(r"[^\d.]", "", line)
            if '.' in line_numbers:
                numbers.append(float(line_numbers))
        if len(numbers) >= 3 and player_number and name:
            numbers_names.update({'player_number': player_number, 'name': name,  'numbers': numbers})
            numbers, player_number, name = [], 0, ''

print(numbers_names)

{'name': 'Marlon Holmes  ', 'numbers': [18.86, 13.02, 13.36], 'player_number': 1}

解析文件的方式：

numbers = [18.86, 13.02, 13.36]

def to_inch(cm):
    return cm/2.54

numbers_in_inches = list(map(to_inch, numbers))
print(numbers_in_inches)

numbers_rounded = list(map(round, numbers_in_inches, [0 for _ in numbers]))
print(numbers_rounded)

sum_numbers = sum(numbers_rounded)
print(sum_numbers)

[7.4251968503937, 5.125984251968504, 5.259842519685039]
[7.0, 5.0, 5.0]
17.0

import re

numbers_names = {}
numbers = []
player_number = ''
name = ''

with open('file.txt', 'r') as f:
    for line in f:
        if '#person number' in line:
            player_number = int(line.split('#')[0])
        elif '#Name' in line:
            name = line.split('#')[0]
        else:
            line_numbers = re.sub(r"[^\d.]", "", line)
            if '.' in line_numbers:
                numbers.append(float(line_numbers))
        if len(numbers) >= 3 and player_number and name:
            numbers_names.update({'player_number': player_number, 'name': name,  'numbers': numbers})
            numbers, player_number, name = [], 0, ''

print(numbers_names)

{'name': 'Marlon Holmes  ', 'numbers': [18.86, 13.02, 13.36], 'player_number': 1}

首先打开文件
接下来迭代文件中的每一行
对于文件中的每一行，它都会查看是一行包含玩家的姓名、玩家编号还是他拥有的编号


Player Number将行拆分为音符，然后数据获取数据并将其设置为等于
Player\u Number

Name将行拆分为注释，然后数据获取数据并将其设置为等于
Name

他拥有的数字它使用
re
的
re.sub（）
删除文件中除
以外的所有非单词字符。然后，检查清理后的行中是否有小数点。最后，如果是这样，它会将该行附加到
numbers

如果这三个值都存在，它会将它们全部附加到
numbers\u names
字典中，并为下一个播放器重置变量

顺便说一句，它是
“%.2f”
。我如何让它与来自该文件的所有数字一起工作？解析该文件并将所有数字放入名为
数字的列表中Updated@NeilHouston您可以将成圆部分添加到
到_inch
中，如下所示：
返回圆（浮动（cm）/2.54,2）
如果您想要2位小数，或者想要最小化浮点舍入问题的任何其他数字，则可以使用2代替总和