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authorPeter Breitenlohner <peb@mppmu.mpg.de>2015-03-20 07:58:39 +0000
committerPeter Breitenlohner <peb@mppmu.mpg.de>2015-03-20 07:58:39 +0000
commit49256ac120db7b7f06e54a931701fe8b3d2b4bdb (patch)
tree3d960eb9207936a77f4b3ef1be06dcf6c61056cd /Build/source/texk/web2c/mplibdir/mpmath.w
parentcae04d40ac09c34e21a3c3efce3ddf43e7062db3 (diff)
texk/web2c/mplibdir: Sync with metapost-trunk
git-svn-id: svn://tug.org/texlive/trunk@36569 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Build/source/texk/web2c/mplibdir/mpmath.w')
-rw-r--r--Build/source/texk/web2c/mplibdir/mpmath.w67
1 files changed, 65 insertions, 2 deletions
diff --git a/Build/source/texk/web2c/mplibdir/mpmath.w b/Build/source/texk/web2c/mplibdir/mpmath.w
index 82d41746c72..b7d1948ec3e 100644
--- a/Build/source/texk/web2c/mplibdir/mpmath.w
+++ b/Build/source/texk/web2c/mplibdir/mpmath.w
@@ -1,4 +1,4 @@
-% $Id: mpmath.w 2037 2014-09-02 14:59:07Z luigi $
+% $Id: mpmath.w 2057 2015-03-20 01:33:59Z luigi $
%
% This file is part of MetaPost;
% the MetaPost program is in the public domain.
@@ -56,6 +56,7 @@ static void mp_number_angle_to_scaled (mp_number *A);
static void mp_number_fraction_to_scaled (mp_number *A);
static void mp_number_scaled_to_fraction (mp_number *A);
static void mp_number_scaled_to_angle (mp_number *A);
+static void mp_m_norm_rand (MP mp, mp_number *ret);
static void mp_m_exp (MP mp, mp_number *ret, mp_number x_orig);
static void mp_m_log (MP mp, mp_number *ret, mp_number x_orig);
static void mp_pyth_sub (MP mp, mp_number *r, mp_number a, mp_number b);
@@ -253,6 +254,7 @@ void * mp_initialize_scaled_math (MP mp) {
math->n_arg = mp_n_arg;
math->m_log = mp_m_log;
math->m_exp = mp_m_exp;
+ math->m_norm_rand = mp_m_norm_rand;
math->pyth_add = mp_pyth_add;
math->pyth_sub = mp_pyth_sub;
math->fraction_to_scaled = mp_number_fraction_to_scaled;
@@ -1816,4 +1818,65 @@ char * mp_number_tostring (MP mp, mp_number n) {
@ @c
void mp_number_modulo (mp_number *a, mp_number b) {
a->data.val = a->data.val % b.data.val;
-} \ No newline at end of file
+}
+
+
+
+
+
+@ To consume a random fraction, the program below will say `|next_random|'.
+
+@c
+static void mp_next_random (MP mp, mp_number *ret) {
+ if ( mp->j_random==0 )
+ mp_new_randoms(mp);
+ else
+ mp->j_random = mp->j_random-1;
+ mp_number_clone (ret, mp->randoms[mp->j_random]);
+}
+
+
+
+@ Finally, a normal deviate with mean zero and unit standard deviation
+can readily be obtained with the ratio method (Algorithm 3.4.1R in
+{\sl The Art of Computer Programming\/}).
+
+@c
+static void mp_m_norm_rand (MP mp, mp_number *ret) {
+ mp_number ab_vs_cd;
+ mp_number abs_x;
+ mp_number u;
+ mp_number r;
+ mp_number la, xa;
+ new_number (ab_vs_cd);
+ new_number (la);
+ new_number (xa);
+ new_number (abs_x);
+ new_number (u);
+ new_number (r);
+ do {
+ do {
+ mp_number v;
+ new_number (v);
+ mp_next_random(mp, &v);
+ mp_number_substract (&v, ((math_data *)mp->math)->fraction_half_t);
+ mp_number_take_fraction (mp,&xa, ((math_data *)mp->math)->sqrt_8_e_k, v);
+ free_number (v);
+ mp_next_random(mp, &u);
+ mp_number_clone (&abs_x, xa);
+ mp_number_abs (&abs_x);
+ } while (!mp_number_less(abs_x, u));
+ mp_number_make_fraction (mp, &r, xa, u);
+ mp_number_clone (&xa, r);
+ mp_m_log (mp,&la, u);
+ mp_set_number_from_substraction(&la, ((math_data *)mp->math)->twelve_ln_2_k, la);
+ mp_ab_vs_cd (mp,&ab_vs_cd, ((math_data *)mp->math)->one_k, la, xa, xa);
+ } while (mp_number_less(ab_vs_cd,((math_data *)mp->math)->zero_t));
+ mp_number_clone (ret, xa);
+ free_number (ab_vs_cd);
+ free_number (r);
+ free_number (abs_x);
+ free_number (la);
+ free_number (xa);
+ free_number (u);
+}