string - Python 2.7 and 3.3.2, why int('0.0') does not work?

Question

As the title says, in Python (I tried in 2.7 and 3.3.2), why int('0.0') does not work? It gives this error:

ValueError: invalid literal for int() with base 10: '0.0'

If you try int('0') or int(eval('0.0')) it works...

Answer 1

From the docs on int:

int(x=0) -> int or long
int(x, base=10) -> int or long

If x is not a number or if base is given, then x must be a string or Unicode object representing an integer literal in the given base.

So, '0.0' is an invalid integer literal for base 10.

You need:

>>> int(float('0.0'))
0

help on int:

>>> print int.__doc__
int(x=0) -> int or long
int(x, base=10) -> int or long

Convert a number or string to an integer, or return 0 if no arguments
are given.  If x is floating point, the conversion truncates towards zero.
If x is outside the integer range, the function returns a long instead.

If x is not a number or if base is given, then x must be a string or
Unicode object representing an integer literal in the given base.  The
literal can be preceded by '+' or '-' and be surrounded by whitespace.
The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
4