At long last, import the bcmath library, by Phil Nelson

2025-08-21 01:45:16 +02:00 · 2000-11-22 20:20:02 +00:00 · 2000-11-22 20:20:02 +00:00 · c476bce2f1
commit c476bce2f1
parent be6ab20415
50 changed files with 6932 additions and 67 deletions
--- a/ext/bcmath/libbcmath/src/raise.c
+++ b/ext/bcmath/libbcmath/src/raise.c
@ -0,0 +1,126 @@
+/* raise.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"
+
+
+/* Raise NUM1 to the NUM2 power.  The result is placed in RESULT.
+   Maximum exponent is LONG_MAX.  If a NUM2 is not an integer,
+   only the integer part is used.  */
+
+void
+bc_raise (num1, num2, result, scale)
+     bc_num num1, num2, *result;
+     int scale;
+{
+   bc_num temp, power;
+   long exponent;
+   int rscale;
+   int pwrscale;
+   int calcscale;
+   char neg;
+
+   /* Check the exponent for scale digits and convert to a long. */
+   if (num2->n_scale != 0)
+     bc_rt_warn ("non-zero scale in exponent");
+   exponent = bc_num2long (num2);
+   if (exponent == 0 && (num2->n_len > 1 || num2->n_value[0] != 0))
+       bc_rt_error ("exponent too large in raise");
+
+   /* Special case if exponent is a zero. */
+   if (exponent == 0)
+     {
+       bc_free_num (result);
+       *result = bc_copy_num (_one_);
+       return;
+     }
+
+   /* Other initializations. */
+   if (exponent < 0)
+     {
+       neg = TRUE;
+       exponent = -exponent;
+       rscale = scale;
+     }
+   else
+     {
+       neg = FALSE;
+       rscale = MIN (num1->n_scale*exponent, MAX(scale, num1->n_scale));
+     }
+
+   /* Set initial value of temp.  */
+   power = bc_copy_num (num1);
+   pwrscale = num1->n_scale;
+   while ((exponent & 1) == 0)
+     {
+       pwrscale = 2*pwrscale;
+       bc_multiply (power, power, &power, pwrscale);
+       exponent = exponent >> 1;
+     }
+   temp = bc_copy_num (power);
+   calcscale = pwrscale;
+   exponent = exponent >> 1;
+
+   /* Do the calculation. */
+   while (exponent > 0)
+     {
+       pwrscale = 2*pwrscale;
+       bc_multiply (power, power, &power, pwrscale);
+       if ((exponent & 1) == 1) {
+	 calcscale = pwrscale + calcscale;
+	 bc_multiply (temp, power, &temp, calcscale);
+       }
+       exponent = exponent >> 1;
+     }
+
+   /* Assign the value. */
+   if (neg)
+     {
+       bc_divide (_one_, temp, result, rscale);
+       bc_free_num (&temp);
+     }
+   else
+     {
+       bc_free_num (result);
+       *result = temp;
+       if ((*result)->n_scale > rscale)
+	 (*result)->n_scale = rscale;
+     }
+   bc_free_num (&power);
+}
+