distinction between float & int

Steve Holden steve at holdenweb.com
Fri Dec 3 15:09:08 CET 2004


Ishwor wrote:

> hi all,
>  can anyone tell me why this distinction? i mean why it returns False
> on floats??
> 
>>>>a = 1
>>>>b = 1
>>>>a is b
> 
> True
> 
>>>>a = 1.1
>>>>b = 1.1
>>>>a is b
> 
> False
> 
> 
> thanx .

There is no guarantee that this will hold in all implementations of Python.

The majority implementation, usually called CPython because its 
implementation language is C, keeps copies of the first 100 (?) integers 
so it doesn't have to create separate integer objects each time they are 
required.

No caching at all is applied to floats, as far as I can tell.

 >>> a = 250
 >>> b = 250
 >>> a is b
False

regards
  Steve

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