代码示例:(标识:eg_js_math_abs)
<!DOCTYPE html>
<html>
<body>

<h1>JavaScript Math.abs()</h1>

<p>Math.abs(x) 返回 x 的绝对值:</p>

<p id="demo"></p>

<script>
document.getElementById("demo").innerHTML = Math.abs(-4.4);
</script>

</body>
</html>
运行结果: