Python 将浮点数转换为美元和美分
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Converting Float to Dollars and Cents
提问by Evorlor
First of all, I have tried this post (among others): Currency formatting in Python. It has no affect on my variable. My best guess is that it is because I am using Python 3 and that was code for Python 2. (Unless I overlooked something, because I am new to Python).
首先，我尝试了这篇文章（以及其他文章）：Python 中的货币格式。它对我的变量没有影响。我最好的猜测是因为我使用的是 Python 3 而那是 Python 2 的代码。（除非我忽略了一些东西，因为我是 Python 新手）。
I want to convert a float, such as 1234.5, to a String, such as "$1,234.50". How would I go about doing this?
我想将浮点数（例如 1234.5）转换为字符串，例如“$1,234.50”。我该怎么做呢？
And just in case, here is my code which compiled, but did not affect my variable:
以防万一，这是我编译的代码，但没有影响我的变量：
money = float(1234.5)
locale.setlocale(locale.LC_ALL, '')
locale.currency(money, grouping=True)
Also unsuccessful:
也失败了：
money = float(1234.5)
print(money) #output is 1234.5
'${:,.2f}'.format(money)
print(money) #output is 1234.5
采纳答案by π?δα? ?κ??
In Python 3.x and 2.7, you can simply do this:
在 Python 3.x 和 2.7 中，您可以简单地执行以下操作：
>>> '${:,.2f}'.format(1234.5)
',234.50'
The :,adds a comma as a thousands separator, and the .2flimits the string to two decimal places (or adds enough zeroes to get to 2 decimal places, as the case may be) at the end.
在:,增加了一个逗号作为千位分隔符，和.2f字符串限制到小数点后两位（或添加足够的零去小数点后2位，视情况而定）在最后。
回答by Alec
Building on @JustinBarber's example and noting @eric.frederich's comment, if you want to format negative values like -$1,000.00rather than $-1,000.00and don't want to use locale:
以@JustinBarber 的例子为基础，并注意@eric.frederich 的评论，如果你想格式化负值，比如-$1,000.00而不是$-1,000.00并且不想使用locale：
def as_currency(amount):
if amount >= 0:
return '${:,.2f}'.format(amount)
else:
return '-${:,.2f}'.format(-amount)
回答by Lewis
In python 3, you can use:
在python 3中，您可以使用：
import locale
locale.setlocale( locale.LC_ALL, 'English_United States.1252' )
locale.currency( 1234.50, grouping = True )
Output
输出
',234.50'
回答by Ariel Robaldo
you said that:
你之前这么说：
`mony = float(1234.5)
print(money) #output is 1234.5
'${:,.2f}'.format(money)
print(money)
did not work.... Have you coded exactly that way? This should work (see the little difference):
没有用......你是否完全那样编码？这应该有效（请参阅细微差别）：
money = float(1234.5) #next you used format without printing, nor affecting value of "money"
amountAsFormattedString = '${:,.2f}'.format(money)
print( amountAsFormattedString )
回答by Rich Bayless
Personally, I like this much better (which, granted, is just a different way of writing the currently selected "best answer"):
就我个人而言，我更喜欢这个（当然，这只是编写当前选择的“最佳答案”的另一种方式）：
money = float(1234.5)
print('$' + format(money, ',.2f'))
Or, if you REALLY don't like "adding" multiple strings to combine them, you could do this instead:
或者，如果你真的不喜欢“添加”多个字符串来组合它们，你可以这样做：
money = float(1234.5)
print('df_buy['BUY'] = df_buy['BUY'].astype('float')
df_buy['BUY'] = [' {:,.2f}'.format(i) for i in list(df_buy['BUY'])]
'.format(format(money, ',.2f')))
I just think both of these styles are a bit easier to read. :-)
我只是觉得这两种风格都更容易阅读。:-)
(of course, you can still incorporate an If-Else to handle negative values as Eric suggests too)
（当然，你仍然可以像 Eric 建议的那样合并一个 If-Else 来处理负值）
