asin
(PHP 4, PHP 5, PHP 7, PHP 8)
asin — 反正弦
说明
asin(float
$arg): float
返回 arg 的反正弦值，单位是弧度。asin()
是 sin() 的反函数，它的意思是在
asin() 范围里的每个值都是
a==sin(asin(a)) 。
参数
-
arg -
待处理的参数
返回值
arg 的反正弦弧度。
add a note
User Contributed Notes 1 note
rahmatjon at gmail dot com ¶
1 year ago
Hello!
Please put this example below the asin() function's description.
Thank you!
Example:
<?php
$arg = 0.5;
$val = asin($arg);
echo "asin(" . $arg . ") = " . $val . " radians.<br/>";
echo "Pi value = " . pi() . "<br/>";
echo "asin(" . $arg . ") = " . $val/pi()*180 . " degrees<br/>";
$arg = 1;
$val = asin($arg);
echo "asin(" . $arg . ") = " . $val . " radians.<br/>";
echo "Pi value = " . pi() . "<br/>";
echo "asin(" . $arg . ") = " . $val/pi()*180 . " degrees<br/>";
?>