[Gmp-commit] /var/hg/gmp-proj/mini-gmp: Implemented mpz_lcm and mpz_lcm_ui.

[mercurial at gmplib.org]

details:   /var/hg/gmp-proj/mini-gmp/rev/a861f07d4d31
changeset: 69:a861f07d4d31
user:      Marco Bodrato <bodrato at mail.dm.unipi.it>
date:      Thu Jan 12 09:29:17 2012 +0100
description:
Implemented mpz_lcm and mpz_lcm_ui.

diffstat:

 mini-gmp.c     |  38 ++++++++++++++++++++++++++++++++++++--
 tests/Makefile |   2 +-
 2 files changed, 37 insertions(+), 3 deletions(-)

diffs (67 lines):

diff -r c3896920ac38 -r a861f07d4d31 mini-gmp.c
--- a/mini-gmp.c	Thu Jan 12 09:08:27 2012 +0100
+++ b/mini-gmp.c	Thu Jan 12 09:29:17 2012 +0100
@@ -40,8 +40,6 @@
      mpz_fdiv_q_2exp
      mpz_fdiv_r_2exp
      mpz_import
-     mpz_lcm
-     mpz_lcm_ui
      mpz_scan0
      mpz_scan1.
 */
@@ -2662,6 +2660,42 @@
   mpz_clear (t1);
 }
 
+void
+mpz_lcm (mpz_t r, const mpz_t u, const mpz_t v)
+{
+  mpz_t g;
+
+  if (u->_mp_size == 0 || v->_mp_size == 0)
+    {
+      r->_mp_size = 0;
+      return;
+    }
+
+  mpz_init (g);
+
+  mpz_gcd (g, u, v);
+  mpz_divexact (g, u, g);
+  mpz_mul (r, g, v);
+
+  mpz_clear (g);
+  mpz_abs (r, r);
+}
+
+void
+mpz_lcm_ui (mpz_t r, const mpz_t u, unsigned long v)
+{
+  if (v == 0 || u->_mp_size == 0)
+    {
+      r->_mp_size = 0;
+      return;
+    }
+
+  v /= mpz_gcd_ui (NULL, u, v);
+  mpz_mul_ui (r, u, v);
+
+  mpz_abs (r, r);
+}
+
 int
 mpz_invert (mpz_t r, const mpz_t u, const mpz_t m)
 {
diff -r c3896920ac38 -r a861f07d4d31 tests/Makefile
--- a/tests/Makefile	Thu Jan 12 09:08:27 2012 +0100
+++ b/tests/Makefile	Thu Jan 12 09:29:17 2012 +0100
@@ -33,7 +33,7 @@
 	$(CC) $(LDFLAGS) $^ $(LIBS) -o $@
 
 # Missing tests include:
-#   mpz_cmp_d, mpz_popcount, mpz_hamdist, mpz_ui_pow_ui
+#   mpz_cmp_d, mpz_popcount, mpz_hamdist, mpz_ui_pow_ui, mpz_lcm
 
 check: $(CHECK_PROGRAMS)
 	./run-tests $(CHECK_PROGRAMS)