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Release calc version 2.12.0

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This commit is contained in:
Landon Curt Noll
2006-05-21 01:11:18 -07:00
parent 7165fa17c7
commit 58d94b08d8
342 changed files with 8845 additions and 6327 deletions
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89
qtrans.c
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@@ -19,8 +19,8 @@
* received a copy with calc; if not, write to Free Software Foundation, Inc.
* 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
*
* @(#) $Revision: 29.6 $
* @(#) $Id: qtrans.c,v 29.6 2004/10/23 00:58:59 chongo Exp $
* @(#) $Revision: 29.7 $
* @(#) $Id: qtrans.c,v 29.7 2006/05/07 13:04:18 chongo Exp $
* @(#) $Source: /usr/local/src/cmd/calc/RCS/qtrans.c,v $
*
* Under source code control: 1990/02/15 01:48:22
@@ -41,6 +41,12 @@ HALF _qlgenum_[] = { 36744 };
HALF _qlgeden_[] = { 25469 };
NUMBER _qlge_ = { { _qlgenum_, 1, 0 }, { _qlgeden_, 1, 0 }, 1, NULL };
/*
* cache the natural logarithm of 10
*/
static NUMBER *ln_10 = NULL;
static NUMBER *ln_10_epsilon = NULL;
static NUMBER *pivalue[2];
static NUMBER *qexprel(NUMBER *q, long bitnum);
@@ -910,7 +916,7 @@ qln(NUMBER *q, NUMBER *epsilon)
BOOL neg;
if (qiszero(q) || qiszero(epsilon)) {
math_error("Zero argument for qln");
math_error("logarithm of 0");
/*NOTREACHED*/
}
if (qisunit(q))
@@ -1007,6 +1013,83 @@ qln(NUMBER *q, NUMBER *epsilon)
}
/*
* Calculate the base 10 logarithm
*
* log(q) = ln(q) / ln(10)
*/
NUMBER *
qlog(NUMBER *q, NUMBER *epsilon)
{
int need_new_ln_10 = TRUE; /* FALSE => use cached ln_10 value */
NUMBER *ln_q; /* ln(x) */
NUMBER *ret; /* base 10 logarithm of x */
/* firewall */
if (qiszero(q) || qiszero(epsilon)) {
math_error("logarithm of 0");
/*NOTREACHED*/
}
/*
* shortcut for small integer powers of 10
*/
if (qisint(q) && qispos(q) && !zge8192b(q->num) && ziseven(q->num)) {
BOOL is_10_power; /* TRUE ==> q is a power of 10 */
long ilog_10; /* integer log base 10 */
/* try for a quick small power of 10 log */
ilog_10 = zlog10(q->num, &is_10_power );
if (is_10_power == TRUE) {
/* is small power of 10, return log */
return itoq(ilog_10);
}
/* q is an even integer that is not a power of 10 */
}
/*
* compute ln(c) first
*/
ln_q = qln(q, epsilon);
/* log(1) == 0 */
if (qiszero(ln_q)) {
return ln_q;
}
/*
* save epsilon for ln(10) if needed
*/
if (ln_10_epsilon == NULL) {
/* first time call */
ln_10_epsilon = qcopy(epsilon);
} else if (qcmp(ln_10_epsilon, epsilon) == FALSE) {
/* replaced cacheed value with epsilon arg */
qfree(ln_10_epsilon);
ln_10_epsilon = qcopy(epsilon);
} else if (ln_10 != NULL) {
/* the previously computed ln(2) is OK to use */
need_new_ln_10 = FALSE;
}
/*
* compute ln(10) if needed
*/
if (need_new_ln_10 == TRUE) {
if (ln_10 != NULL) {
qfree(ln_10);
}
ln_10 = qln(&_qten_, ln_10_epsilon);
}
/*
* return ln(q) / ln(10)
*/
ret = qqdiv(ln_q, ln_10);
qfree(ln_q);
return ret;
}
/*
* Calculate the result of raising one number to the power of another.
* The result is calculated to the nearest or next to nearest multiple of