4.3: Type Conversion Functions
- Page ID
- 3045
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Python also provides built-in functions that convert values from one type to another. The int
function takes any value and converts it to an integer, if it can, or complains otherwise:
>>> int('32')
32
>>> int('Hello')
ValueError: invalid literal for int() with base 10: 'Hello'
int
can convert floating-point values to integers, but it doesn't round off; it chops off the fraction part:
>>> int(3.99999)
3
>>> int(-2.3)
-2
float
converts integers and strings to floating-point numbers:
>>> float(32)
32.0
>>> float('3.14159')
3.14159
Finally, str
converts its argument to a string:
>>> str(32)
'32'
>>> str(3.14159)
'3.14159'