[Numpy-discussion] Questions about converting to numpy

Robert Kern robert.kern@gmail....
Wed Apr 25 16:31:50 CDT 2007

Christopher Barker wrote:

> I can only help with one:
>> - Even after reading the book I'm not really clear on why one would use 
>> numpy.float_ instead of numpy.float or float
> They float and numpy.float are the same, and numpy.float_ is the same as 
> numpy.float64:
>  >>> import numpy
>  >>> float is numpy.float
> True
>  >>> numpy.float64 is numpy.float64
> True
>  >>>
> float was added to the numpy namespace so that we could write consistent 
> code like:
> a = array(object, numpy.float32)
> b = array(object, numpy.float)
> i.e. have it all in the same namespace.
> I'm not sure why float_ is an alias for float64, though I'm guessing 
> it's possible that on some platforms they are not the same.

Rather, numpy.float used to be an alias for numpy.float64; however, it overrode
the builtin float() when "from numpy import *" was used at the interactive
prompt. Consequently, we renamed it numpy.float_ and specifically imported the
builtin float as numpy.float such that we didn't break code that had already
started using "numpy.float".

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

More information about the Numpy-discussion mailing list