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

Robert Kern robert.kern at
Mon Jun 16 21:57:06 CEST 2008

John [H2O] wrote:
> Dan Bishop wrote:
>> Python just uses the atof() function from the underlying C library.
>> Some of them handle NaN's, and some of them don't.
> As a work around, how would I write this in list comprehension form:
>          newlist=[]
>          for i in range(len(v[1])):
>             try:
>                newlist.append(float(v[1][i]))
>             except:
>                newlist.append(-999.99) # or just nan possibly?

from numpy import nan

def nanfloat(x):
     if x.lower() == 'nan':
         return nan
         return float(x)

newlist = [myfloat(x) for x in v[1]]

Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco

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