Re: numpy: handling float('NaN') different in XP vs. Linux

On Jun 14, 1:45 pm, "John [H2O]" <washa...@xxxxxxxxx> wrote:
I have a script:

from numpy import float
OutD=[]
v=['3','43','23.4','NaN','43']
OutD.append([float(i) for i in v[1]])

On linux:
Python 2.5.1 (r251:54863, Mar 7 2008, 04:10:12)
[GCC 4.1.3 20070929 (prerelease) (Ubuntu 4.1.2-16ubuntu2)] on linux2
[john@andLinux analysis]$ python jnk.py
[[3.0, 43.0, 23.399999999999999, nan, 43.0]]

On XP:
Python 2.5 (r25:51908, Mar 9 2007, 17:40:28) [MSC v.1310 32 bit (Intel)]
Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\analysis>C:\Python25\python.exe jnk.py
Traceback (most recent call last):
File "jnk.py", line 4, in <module>
OutD.append([float(i) for i in v])
ValueError: invalid literal for float(): NaN

WTF?

Avoid impolite astonishment; RTFloatingM instead:
"""
float( [x])

Convert a string or a number to floating point. If the argument is a
string, it must contain a possibly signed decimal or floating point
number, possibly embedded in whitespace. Otherwise, the argument may
be a plain or long integer or a floating point number, and a floating
point number with the same value (within Python's floating point
precision) is returned. If no argument is given, returns 0.0.

Note: When passing in a string, values for NaN and Infinity may be
returned, depending on the underlying C library. The specific set of
strings accepted which cause these values to be returned depends
entirely on the C library and is known to vary.
"""

You may like to suggest a minor extension to the docs: after "is known
to vary" add "and may even be empty".

HTH,
John
.

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