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Subject: Re: [OMPI users] MPI_Allreduce on local machine
From: Terry Frankcombe (terry_at_[hidden])
Date: 2010-07-27 08:17:44


On Tue, 2010-07-27 at 08:11 -0400, Jeff Squyres wrote:
> On Jul 26, 2010, at 11:06 PM, Hugo Gagnon wrote:
>
> > 8 integer, parameter :: dp = kind(1.d0)
> > 9 real(kind=dp) :: inside(5), outside(5)
>
> I'm not a fortran expert -- is kind(1.d0) really double precision? According to http://gcc.gnu.org/onlinedocs/gcc-3.4.6/g77/Kind-Notation.html, kind(2) is double precision (but that's for a different compiler, and I don't quite grok the ".d0" notation).
>

Urgh! Thank heavens gcc have moved away from that stupid idea.

kind=8 is normally double precision (and is with gfortran). kind(1.0d0)
is always double precision.

The d (as opposed to e) means DP.