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/*=============================================================================
This file is part of FLINT.
FLINT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
FLINT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with FLINT; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2012 Fredrik Johansson
******************************************************************************/
#include "double_extras.h"
#include "ulong_extras.h"
#define EXP_MINUS_32 2.3283064365386962891e-10
#define EXP_MINUS_64 5.42101086242752217e-20
double
d_randtest(flint_rand_t state)
{
mp_limb_t m1, m2;
double t;
if (FLINT_BITS == 64)
{
m1 = n_randlimb(state) | (UWORD(1) << (FLINT_BITS - 1));
t = ((double) m1) * EXP_MINUS_64;
}
else
{
m1 = n_randlimb(state) | (UWORD(1) << (FLINT_BITS - 1));
m2 = n_randlimb(state);
t = ((double) m1) * EXP_MINUS_32 +
((double) m2) * EXP_MINUS_64;
}
return t;
}
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