cexp error

[Steve Kargl]

On Fri, Sep 14, 2012 at 07:26:55PM -0500, Stephen Montgomery-Smith wrote:
> On 09/14/2012 01:05 AM, Bruce Evans wrote:
> 
> >My tests also determined the exact minimum for all multiples up to the
> >thresholds for "large" multiples in e_rem_pio2.c, except for ld128,
> >to verify that there are enough bits in the special approximations for
> >Pi/2 there, except for ld128.  The maximum multiples handled there are
> >2**28*Pi/2, except for ld128 they are 2**45*Pi/2.  2**45 is too many
> >to check exhaustively.
> 
> But presumably one could prove a result to this effect using continued 
> fractions, right?
> 

See attached.  It shows a method for determining the number
of needed bits.

-- 
Steve
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