1/* mpfr_dot -- dot product of two array of numbers 2 3Copyright 2018-2023 Free Software Foundation, Inc. 4Contributed by the AriC and Caramba projects, INRIA. 5 6This file is part of the GNU MPFR Library. 7 8The GNU MPFR Library is free software; you can redistribute it and/or modify 9it under the terms of the GNU Lesser General Public License as published by 10the Free Software Foundation; either version 3 of the License, or (at your 11option) any later version. 12 13The GNU MPFR Library is distributed in the hope that it will be useful, but 14WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 15or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 16License for more details. 17 18You should have received a copy of the GNU Lesser General Public License 19along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see 20https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., 2151 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ 22 23#include "mpfr-impl.h" 24 25/* FIXME: handle intermediate overflows and underflows. */ 26 27/* res <- a[0]*b[0] + ... + a[n-1]*b[n-1] */ 28int 29mpfr_dot (mpfr_ptr res, const mpfr_ptr *a, const mpfr_ptr *b, 30 unsigned long n, mpfr_rnd_t rnd) 31{ 32 mpfr_t *c; 33 size_t i; 34 int inex; 35 mpfr_ptr *tab; 36 37 if (MPFR_UNLIKELY (n == 0)) 38 { 39 MPFR_SET_ZERO (res); 40 MPFR_SET_POS (res); 41 MPFR_RET (0); 42 } 43 44 c = (mpfr_t *) mpfr_allocate_func (n * sizeof (mpfr_t)); 45 tab = (mpfr_ptr *) mpfr_allocate_func (n * sizeof (mpfr_ptr)); 46 for (i = 0; i < n; i++) 47 { 48 mpfr_init2 (c[i], mpfr_get_prec (a[i]) + mpfr_get_prec (b[i])); 49 inex = mpfr_mul (c[i], a[i], b[i], MPFR_RNDZ); /* exact except... */ 50 MPFR_ASSERTN (inex == 0); /* failure in case of overflow/underflow */ 51 tab[i] = c[i]; 52 } 53 inex = mpfr_sum (res, tab, n, rnd); 54 for (i = 0; i < n; i++) 55 mpfr_clear (c[i]); 56 mpfr_free_func (c, n * sizeof (mpfr_t)); 57 mpfr_free_func (tab, n * sizeof (mpfr_ptr)); 58 return inex; 59} 60