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Diffstat (limited to 'ext/bcmath/libbcmath/src/sqrt.c')
| -rw-r--r-- | ext/bcmath/libbcmath/src/sqrt.c | 131 |
1 files changed, 0 insertions, 131 deletions
diff --git a/ext/bcmath/libbcmath/src/sqrt.c b/ext/bcmath/libbcmath/src/sqrt.c deleted file mode 100644 index 34b95b8898..0000000000 --- a/ext/bcmath/libbcmath/src/sqrt.c +++ /dev/null @@ -1,131 +0,0 @@ -/* sqrt.c: bcmath library file. */ -/* - Copyright (C) 1991, 1992, 1993, 1994, 1997 Free Software Foundation, Inc. - Copyright (C) 2000 Philip A. Nelson - - This 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 of the License, or (at your option) any later version. - - This 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. (COPYING.LIB) - - You should have received a copy of the GNU Lesser General Public - License along with this library; if not, write to: - - The Free Software Foundation, Inc. - 59 Temple Place, Suite 330 - Boston, MA 02111-1307 USA. - - You may contact the author by: - e-mail: philnelson@acm.org - us-mail: Philip A. Nelson - Computer Science Department, 9062 - Western Washington University - Bellingham, WA 98226-9062 - -*************************************************************************/ - -#include <config.h> -#include <stdio.h> -#include <assert.h> -#include <stdlib.h> -#include <ctype.h> -#include <stdarg.h> -#include "bcmath.h" -#include "private.h" - -/* Take the square root NUM and return it in NUM with SCALE digits - after the decimal place. */ - -int -bc_sqrt (num, scale) - bc_num *num; - int scale; -{ - int rscale, cmp_res, done; - int cscale; - bc_num guess, guess1, point5, diff; - - /* Initial checks. */ - cmp_res = bc_compare (*num, _zero_); - if (cmp_res < 0) - return 0; /* error */ - else - { - if (cmp_res == 0) - { - bc_free_num (num); - *num = bc_copy_num (_zero_); - return 1; - } - } - cmp_res = bc_compare (*num, _one_); - if (cmp_res == 0) - { - bc_free_num (num); - *num = bc_copy_num (_one_); - return 1; - } - - /* Initialize the variables. */ - rscale = MAX (scale, (*num)->n_scale); - bc_init_num(&guess); - bc_init_num(&guess1); - bc_init_num(&diff); - point5 = bc_new_num (1,1); - point5->n_value[1] = 5; - - - /* Calculate the initial guess. */ - if (cmp_res < 0) - { - /* The number is between 0 and 1. Guess should start at 1. */ - guess = bc_copy_num (_one_); - cscale = (*num)->n_scale; - } - else - { - /* The number is greater than 1. Guess should start at 10^(exp/2). */ - bc_int2num (&guess,10); - - bc_int2num (&guess1,(*num)->n_len); - bc_multiply (guess1, point5, &guess1, 0); - guess1->n_scale = 0; - bc_raise (guess, guess1, &guess, 0); - bc_free_num (&guess1); - cscale = 3; - } - - /* Find the square root using Newton's algorithm. */ - done = FALSE; - while (!done) - { - bc_free_num (&guess1); - guess1 = bc_copy_num (guess); - bc_divide (*num, guess, &guess, cscale); - bc_add (guess, guess1, &guess, 0); - bc_multiply (guess, point5, &guess, cscale); - bc_sub (guess, guess1, &diff, cscale+1); - if (bc_is_near_zero (diff, cscale)) - { - if (cscale < rscale+1) - cscale = MIN (cscale*3, rscale+1); - else - done = TRUE; - } - } - - /* Assign the number and clean up. */ - bc_free_num (num); - bc_divide (guess,_one_,num,rscale); - bc_free_num (&guess); - bc_free_num (&guess1); - bc_free_num (&point5); - bc_free_num (&diff); - return 1; -} - |