Definition and Usage
定义与用法

The asin() method returns the arcsine of a number as a numeric value between
-PI/2 and PI/2 radians.
asin()方法可以得到数值的反正弦值

Syntax
语法

Math.asin(x)

Tips and Notes
提示与注意点

Note: If the parameter x is outside the range -1 to 1, the browser will return NaN.
注意：如果参数x的范围超出了-1到1。浏览器会返回NaN

Note: 1 will return the value of PI/2.
注意：参数为1则范围圆周率的一半值

Example
举例

In this example we will get the arcsine of different numbers:
举例中我们将得到不同数字的反正弦值：

<script type="text/javascript">

document.write(Math.asin(0.64) + "<br />")
document.write(Math.asin(0) + "<br />")
document.write(Math.asin(-1) + "<br />")
document.write(Math.asin(1) + "<br />")
document.write(Math.asin(2))

</script>

The output of the code above will be:
输出结果为：

0.6944982656265559
0
-1.5707963267948965
1.5707963267948965
NaN

Try-It-Yourself Demos
尝试与演示

asin()
How to use asin() to get the arcsine of different numbers.
怎样使用asin()来获得不同数字的反正弦值

评论 (0) All