Math.floor() returns int in Windows, but returns double in Linux?!

[pavelexpertov]

Hello, I searched the net to find an answer to this tiny annoyance, but unfortunately I did not find one.
Basically, I was doing some programming in Python 3.3 by writing small algorithms (like zeller one) and I managed to make it work on windows, whereas in Linux, I stumbled upon the problem. Basically I spent 2 hours debugging this thing until I found out that Math.floor() return double value in Linux compared to Windows, where the function returns int!!!! I find it very annoying wasting my time debugging. Anyone who knows about this, please can you explain this to me on why this happens. Thank you.

PS. At least I learned my lesson, should use casting functions next time to make sure the values are right.

[ofnuts]

I wonder what version of Python you are using:


>>>python3
Python 3.2.3 (default, Feb 28 2014, 00:21:38)
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import math
>>> x=math.floor(3.141592654)
>>> print (x)
3
>>> print(type(x))
<class 'int'>


Btw, Python v2 (which is still the default Python in Linux) returns a float in math.floor(), so maybe you are not using Python v3 as you think.

PS: Casting is a bad idea, it just hides the problem until it blows in your face later.

[The Cog]

In python 2.7, math.floor() returns <type 'float'>.

To run python3 in Linux, the command is "python3", not "python". I believe this is part of the python3 specification.

[ssam]

In python 2.7, math.floor() returns <type 'float'>.

To run python3 in Linux, the command is "python3", not "python". I believe this is part of the python3 specification.

python was meant to always give python 2.x, and python3 for python 3.x. But some linux distros (arch) though it would be a good idea to make python point to python 3.x. So its safest to use python2 to get python 2.x (although this may not work on some older linux distros).
http://legacy.python.org/dev/peps/pep-0394/

[pavelexpertov]

Hello, in Linux, I usually type in python3.3, but even if I typed python3, I still get the same new version of python:


pavel@pavel-OptiPlex:~$ python3.3
Python 3.3.2+ (default, Feb 28 2014, 00:53:38)
[GCC 4.8.1] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>


Edit: Weird, I used print(type(var)) to find out what type of value I would get, but unfortunately it's int when using Math.floor(). I need to recheck the code I wrote in the first place.

[pavelexpertov]

Update: I checked my code again and now math.floor() produces int value rather than double. Damn it, and I have seen it produce the double value like 2 days ago. It seems like an old good fix of 'rebooting computer' helps. Thanks for posting guys!!!!!!!!!!!!!!!!!!!!!!!!
plus got rid of casting in it since it's not needed.

[trent.josephsen]

python was meant to always give python 2.x, and python3 for python 3.x. But some linux distros (arch) though it would be a good idea to make python point to python 3.x
The PEP you linked doesn't back up that assertion:


Similarly, the more general python command should be installed whenever any version of Python is installed and should invoke the same version of Python as either python2 or python3.
For the time being, it is recommended that python should refer to python2[...]
[A]ll new code that needs to invoke the Python interpreter should not specify python, but rather should specify either python2 or python3
I'm pretty sure there was never any intention to make python refer to python2 forever.