Compatibility with mpf. WARNING: THESE FUNCTIONS ARE UNTESTED IN THEIR PRESENT

FORM. THEY *DO* COMPILE HOWEVER.


git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@524 280ebfd0-de03-0410-8827-d642c229c3f4

1 files changed, 75 insertions, 0 deletions

diff --git a/urandomb.c b/urandomb.c
new file mode 100644
index 000000000..fd7be497d
--- /dev/null
+++ b/urandomb.c
@@ -0,0 +1,75 @@
+/* mpfr_urandomb (rop, state, nbits) -- Generate a uniform pseudorandom
+   real number between 0 (inclusive) and 1 (exclusive) of size NBITS,
+   using STATE as the random state previously initialized by a call to
+   gmp_randinit().
+
+Copyright (C) 1999, 2000  Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Library General Public License as published by
+the Free Software Foundation; either version 2 of the License, or (at your
+option) any later version.
+
+The GNU MP Library 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 Library General Public
+License for more details.
+
+You should have received a copy of the GNU Library General Public License
+along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+MA 02111-1307, USA. */
+
+#include <stdio.h>
+#include "gmp.h"
+#include "gmp-impl.h"
+#include "mpfr.h"
+
+void
+#if __STDC__
+mpfr_urandomb (mpfr_t rop, gmp_randstate_t rstate, unsigned long int nbits)
+#else
+mpfr_urandomb (rop, rstate, nbits)
+     mpfr_t rop;
+     gmp_randstate_t rstate;
+     unsigned long int nbits;
+#endif
+{
+  mp_ptr rp;
+  mp_size_t nlimbs;
+  mp_exp_t exp;
+  unsigned long cnt; 
+
+  rp = PTR (rop);
+  nlimbs = (nbits + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB;
+
+  _gmp_rand (rp, rstate, nbits);
+
+  /* If nbits isn't a multiple of BITS_PER_MP_LIMB, shift up.  */
+  if (nlimbs != 0)
+    {
+      if (nbits % BITS_PER_MP_LIMB != 0)
+	mpn_lshift (rp, rp, nlimbs,
+		    BITS_PER_MP_LIMB - nbits % BITS_PER_MP_LIMB);
+    }
+
+  exp = 0;
+  while (nlimbs != 0 && rp[nlimbs - 1] == 0)
+    {
+      nlimbs--;
+      exp--;
+    }
+
+  count_leading_zeros(cnt, rp[nlimbs - 1]); 
+  if (cnt) mpn_lshift(rp, rp, nlimbs, cnt); 
+  exp -= cnt; 
+
+  cnt = nlimbs*BITS_PER_MP_LIMB - nbits; 
+  /* cnt is the number of non significant bits in the low limb */
+  rp[0] &= ~((((mp_limb_t)1)<<cnt) - 1);
+
+  EXP (rop) = exp;
+  SIZ (rop) = nlimbs;
+}