[SciPy-user] Re: nan puzzle
Howey, David A
d.howey at imperial.ac.uk
Wed Jul 27 10:57:25 CDT 2005
Just found this, thought it might be of interest-- gurus probably know this already, I wasn't aware:
http://www.cs.ucla.edu/classes/winter04/cs131/hw/hw4.html
Dave
________________________________
From: scipy-user-bounces at scipy.net on behalf of Grant Edwards
Sent: Wed 13/07/2005 05:16
To: scipy-user at scipy.org
Subject: [SciPy-user] Re: nan puzzle
On 2005-07-13, Alan G Isaac <aisaac at american.edu> wrote:
> Is this expected behavior?
>>>> x is nan
> True
>>>> x=z[2]
>>>> x
> -1.#IND
>>>> x is nan
> False
May I ask why you care?
The expression "x is nan" seems pretty useless to me. The "is"
operator isn't really useful for other floating point values,
why would it be useful for nans?
>>> x = 1.234
>>> x is 1.234
False
>>>
>>> y = 1.234
>>> x is y
False
>>> x == y
True
>>>
What you probably want to be checking is if x has a nan value,
not whether x is the same object as some other object that
has a nan value.
--
Grant Edwards grante Yow! Is this my STOP??
at
visi.com
_______________________________________________
SciPy-user mailing list
SciPy-user at scipy.net
http://www.scipy.net/mailman/listinfo/scipy-user
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/ms-tnef
Size: 5164 bytes
Desc: not available
Url : http://www.scipy.net/pipermail/scipy-user/attachments/20050727/71fdba84/attachment.bin
More information about the SciPy-user
mailing list