Message-ID: <4A0320A3.2010502@biostat.ku.dk>
Date: 2009-05-07T17:55:47Z
From: Peter Dalgaard
Subject: 64 bit R double precision
In-Reply-To: <4A0312A9.3050904@calidasoft.co.uk>
Paul Emberson wrote:
> Hi,
>
> If R is compiled for a 64 bit platform, does the double data type make
> use of the additional precision or is it set at a fixed length?
No. Double is double, 64 bits, although sometimes 80 bits when things
are kept in registers. However, even though the FPU is identical between
64 and 32 bit machines, you do not in general get the same results, due
to tricks played by optimizing compilers.
--
O__ ---- Peter Dalgaard ?ster Farimagsgade 5, Entr.B
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