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diff --git a/Build/source/libs/mpfi/mpfi-src/src/cot.c b/Build/source/libs/mpfi/mpfi-src/src/cot.c
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+/* cot.c -- Cotangent of an interval.
+
+Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2010,
+ Spaces project, Inria Lorraine
+ and Salsa project, INRIA Rocquencourt,
+ and Arenaire project, Inria Rhone-Alpes, France
+ and Lab. ANO, USTL (Univ. of Lille), France
+
+This file is part of the MPFI Library.
+
+The MPFI Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or (at your
+option) any later version.
+
+The MPFI 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 Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the MPFI Library; see the file COPYING.LIB. If not, write to
+the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+MA 02110-1301, USA. */
+
+#include "mpfi-impl.h"
+
+int
+mpfi_cot (mpfi_ptr a, mpfi_srcptr b)
+{
+ int inexact_left, inexact_right, inexact=0;
+ mpz_t z_left, z_right, z;
+
+ if (MPFI_NAN_P (b)) {
+ mpfr_set_nan (&(a->left));
+ mpfr_set_nan (&(a->right));
+ MPFR_RET_NAN;
+ }
+
+ if (MPFI_INF_P (b)) {
+ /* the two endpoints are the same infinite */
+ if (mpfr_cmp (&(b->left), &(b->right)) == 0) {
+ mpfr_set_nan (&(a->left));
+ mpfr_set_nan (&(a->right));
+ MPFR_RET_NAN;
+ }
+ mpfr_set_inf (&(a->left), -1);
+ mpfr_set_inf (&(a->right), 1);
+ return 0;
+ }
+
+ mpz_init (z_left);
+ mpz_init (z_right);
+ mpz_init (z);
+
+ mpfi_quadrant (z_left, &(b->left));
+ mpfi_quadrant (z_right, &(b->right));
+ mpz_sub (z, z_right, z_left);
+
+ if (mpfr_zero_p (&(b->left)) || mpfr_zero_p (&(b->right))) {
+ /* one end point is zero, this is the only multiple of Pi to be exact */
+ if (mpfr_zero_p (&(b->left)) && mpfr_zero_p (&(b->right))) {
+ /* cot([+0, -0] = [NaN, NaN] */
+ mpfr_set_nan (&(a->left));
+ mpfr_set_nan (&(a->right));
+ MPFR_RET_NAN;
+ }
+
+ if ((mpfr_zero_p (&(b->left)) && mpz_cmp_ui (z_right, 1) > 0)
+ || (mpfr_zero_p (&(b->right)) && mpz_cmp_si (z_left, -2) < 0)) {
+ /* b contains more than one period */
+ mpfr_set_inf (&(a->left), -1);
+ mpfr_set_inf (&(a->right), 1);
+ inexact = 0;
+ }
+ else if (mpfr_zero_p (&(b->left))) {
+ /* cot([+0, x]) = [cot(x), +oo] */
+ inexact_left = mpfr_cot (&(a->left), &(b->right), MPFI_RNDD);
+ inexact = inexact_left ? MPFI_FLAGS_LEFT_ENDPOINT_INEXACT : 0;
+ mpfr_set_inf (&(a->right), 1);
+ }
+ else {
+ /* cot([x, -0]) = [-oo, cot(x)] */
+ inexact_right = mpfr_cot (&(a->right), &(b->left), MPFI_RNDU);
+ inexact = inexact_right ? MPFI_FLAGS_RIGHT_ENDPOINT_INEXACT : 0;
+ mpfr_set_inf (&(a->left), -1);
+ }
+ }
+ else if ((mpz_cmp_ui (z, 2) >= 0)
+ || (mpz_odd_p (z_left) && mpz_even_p (z_right))) {
+ /* there is at least one period in b or if b contains a k*Pi, */
+ /* then a = ]-oo, +oo[ */
+ mpfr_set_inf (&(a->left), -1);
+ mpfr_set_inf (&(a->right), 1);
+ inexact = 0;
+ }
+ else { /* within one period, cot is decreasing */
+ mpfr_t tmp;
+
+ mpfr_init2 (tmp, mpfr_get_prec (&(a->left)));
+ inexact_left = mpfr_cot (tmp, &(b->right), MPFI_RNDD);
+ inexact_right = mpfr_cot (&(a->right), &(b->left), MPFI_RNDU);
+ mpfr_set (&(a->left), tmp, MPFI_RNDD); /* exact */
+ mpfr_clear (tmp);
+
+ if (inexact_left) inexact += 1;
+ if (inexact_right) inexact += 2;
+ }
+
+ mpz_clear (z_left);
+ mpz_clear (z_right);
+ mpz_clear (z);
+
+ return inexact;
+}