summaryrefslogtreecommitdiff
path: root/libguile/integers.c
diff options
context:
space:
mode:
Diffstat (limited to 'libguile/integers.c')
-rw-r--r--libguile/integers.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/libguile/integers.c b/libguile/integers.c
index d318fd775..2fde52625 100644
--- a/libguile/integers.c
+++ b/libguile/integers.c
@@ -3074,3 +3074,76 @@ scm_integer_exact_sqrt_z (struct scm_bignum *k, SCM *s, SCM *r)
*s = take_mpz (zs);
*r = take_mpz (zr);
}
+
+int
+scm_is_integer_perfect_square_i (scm_t_inum k)
+{
+ if (k < 0)
+ return 0;
+ if (k == 0)
+ return 1;
+ mp_limb_t kk = k;
+ return mpn_perfect_square_p (&kk, 1);
+}
+
+int
+scm_is_integer_perfect_square_z (struct scm_bignum *k)
+{
+ mpz_t zk;
+ alias_bignum_to_mpz (k, zk);
+ int result = mpz_perfect_square_p (zk);
+ scm_remember_upto_here_1 (k);
+ return result;
+}
+
+SCM
+scm_integer_floor_sqrt_i (scm_t_inum k)
+{
+ if (k <= 0)
+ return SCM_INUM0;
+
+ mp_limb_t kk = k, ss;
+ mpn_sqrtrem (&ss, NULL, &kk, 1);
+ return SCM_I_MAKINUM (ss);
+}
+
+SCM
+scm_integer_floor_sqrt_z (struct scm_bignum *k)
+{
+ mpz_t zk, zs;
+ alias_bignum_to_mpz (k, zk);
+ mpz_init (zs);
+ mpz_sqrt (zs, zk);
+ scm_remember_upto_here_1 (k);
+ return take_mpz (zs);
+}
+
+double
+scm_integer_inexact_sqrt_i (scm_t_inum k)
+{
+ if (k < 0)
+ return -sqrt ((double) -k);
+ return sqrt ((double) k);
+}
+
+double
+scm_integer_inexact_sqrt_z (struct scm_bignum *k)
+{
+ mpz_t zk, zs;
+ alias_bignum_to_mpz (k, zk);
+ mpz_init (zs);
+
+ long expon;
+ double signif = bignum_frexp (k, &expon);
+ int negative = signif < 0;
+ if (negative)
+ signif = -signif;
+
+ if (expon & 1)
+ {
+ signif *= 2;
+ expon--;
+ }
+ double result = ldexp (sqrt (signif), expon / 2);
+ return negative ? -result : result;
+}