How do I convert a string to a double in Python?

问题:

I would like to know how to convert a string containing digits to a double.

回答1:

>>> x = "2342.34" >>> float(x) 2342.3400000000001 

There you go. Use float (which is almost always a C double).

回答2:

The decimal operator might be more in line with what you are looking for:

>>> from decimal import Decimal >>> x = "234243.434" >>> print Decimal(x) 234243.434 

回答3:

Be aware that if your string number contains more than 15 significant digits float(s) will round it.In those cases it is better to use Decimal

Here is an explanation and some code samples: https://docs.python.org/3/library/sys.html#sys.float_info

文章来源: How do I convert a string to a double in Python?