jason Mon Nov 11 00:21:35 2002 EDT
Modified files:
/php4/ext/standard math.c
/php4/ext/standard/tests/math log.phpt
Log:
Add the ability to take the logarithm of any base by adding a base parameter
to log()
Added regression tests for the new form
Index: php4/ext/standard/math.c
diff -u php4/ext/standard/math.c:1.93 php4/ext/standard/math.c:1.94
--- php4/ext/standard/math.c:1.93 Thu Oct 24 15:15:40 2002
+++ php4/ext/standard/math.c Mon Nov 11 00:21:35 2002
@@ -19,7 +19,7 @@
+----------------------------------------------------------------------+
*/
-/* $Id: math.c,v 1.93 2002/10/24 19:15:40 helly Exp $ */
+/* $Id: math.c,v 1.94 2002/11/11 05:21:35 jason Exp $ */
#include "php.h"
#include "php_math.h"
@@ -520,19 +520,35 @@
/* }}} */
#endif
-/* {{{ proto float log(float number)
- Returns the natural logarithm of the number */
+/* {{{ proto float log(float number, [float base])
+ Returns the natural logarithm of the number, or the base log if base is specified
+*/
PHP_FUNCTION(log)
{
- zval **num;
-
- if (ZEND_NUM_ARGS() != 1 || zend_get_parameters_ex(1, &num) == FAILURE) {
- WRONG_PARAM_COUNT;
+ zval **num, **base;
+
+ switch (ZEND_NUM_ARGS()) {
+ case 1:
+ if (zend_get_parameters_ex(1, &num) == FAILURE) {
+ WRONG_PARAM_COUNT;
+ }
+ convert_to_double_ex(num);
+ RETURN_DOUBLE(log(Z_DVAL_PP(num)));
+ case 2:
+ if (zend_get_parameters_ex(2, &num, &base) == FAILURE) {
+ WRONG_PARAM_COUNT;
+ }
+ convert_to_double_ex(num);
+ convert_to_double_ex(base);
+
+ if (Z_DVAL_PP(base) <= 0.0) {
+ php_error(E_WARNING, "base must be greater than 0",
+Z_DVAL_PP(base));
+ RETURN_FALSE;
+ }
+ RETURN_DOUBLE(log(Z_DVAL_PP(num)) / log(Z_DVAL_PP(base)));
+ default:
+ WRONG_PARAM_COUNT;
}
- convert_to_double_ex(num);
- Z_DVAL_P(return_value) = log(Z_DVAL_PP(num));
- Z_TYPE_P(return_value) = IS_DOUBLE;
}
/* }}} */
Index: php4/ext/standard/tests/math/log.phpt
diff -u php4/ext/standard/tests/math/log.phpt:1.1
php4/ext/standard/tests/math/log.phpt:1.2
--- php4/ext/standard/tests/math/log.phpt:1.1 Sun Nov 10 22:45:04 2002
+++ php4/ext/standard/tests/math/log.phpt Mon Nov 11 00:21:35 2002
@@ -3,19 +3,42 @@
--POST--
--GET--
--FILE--
-<?php // $Id: log.phpt,v 1.1 2002/11/11 03:45:04 jason Exp $
+<?php // $Id: log.phpt,v 1.2 2002/11/11 05:21:35 jason Exp $
echo "On failure, please mail result to [EMAIL PROTECTED]\n";
-for ($x=0, $count=0; $x < 200; $x++) {
+for ($x = 0, $count= 0; $x < 200; $x++) {
$x2 = (int) exp(log($x));
// e ^ log(x) should be close in range to x
if (($x2 < ($x + 2)) && ($x2 > ($x - 2))) {
$count++;
- }
- else {
+ } else {
print "$x : $x2\n";
}
}
print $count . "\n";
+
+// Now test the base form of log
+for ($base = 2; $base < 11; $base++) {
+ for ($x = 0, $count= 0; $x < 50; $x++) {
+ $x2 = (int) pow($base, log($x, $base));
+ // base ^ log(x) should be close in range to x
+ if (($x2 < ($x + 2)) && ($x2 > ($x - 2))) {
+ $count++;
+ } else {
+ print "base $base: $x : $x2\n";
+ }
+ }
+ print $count . "\n";
+}
+?>
--EXPECT--
On failure, please mail result to [EMAIL PROTECTED]
200
+50
+50
+50
+50
+50
+50
+50
+50
+50
--
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