Re: [Numpy-discussion] array from list of lists

[Charles R H. <cha...@gm...>]

On 11/12/06, Erin Sheldon <eri...@gm...> wrote:
>
> On 11/12/06, Erin Sheldon <eri...@gm...> wrote:
> > On 11/12/06, Pierre GM <pgm...@gm...> wrote:
> > >
> > > You could try the fromarrays function of numpy.core.records
> > >
> > > >>> mydescriptor = {'names': (a','b','c','d'), 'formats':('f4', 'f4',
> 'f4',
> > > 'f4')}
> > > >>> a = N.core.records.fromarrays(N.transpose(yourlist),
> dtype=mydescriptor)
> > >
> > > The 'transpose' function ensures that 'fromarrays' sees 4 arrays (one
> for each
> > > column).
>
> Actually, there is a problem with that approach.  It first converts
> the entire array to a single type, by default a floating type.  For
> very large integers this precision is insufficient.  For example, I
> have the following integer in my arrays:
> 94137100072000193L
> which ends up as
>   94137100072000192
> after going to a float and then back to an integer.


Out of curiosity, where does that large integer come from?

Chuck