莊秀慧 w3schools物件object亂數random進為ceil捨去floor

教學影片343,344,345

莊秀慧JavaScript語言Math數學方法(內建函數)

輸入數字N

Math.random()亂數Method產生0(含)到N(不含)

Math.floor()無條件捨去Method

Math.ceil()進位Method

Math.round()四捨Method

以上程式碼在撰寫模式貼上

<h1>莊秀慧JavaScript語言Math數學方法(內建函數)</h1>

<h2>Math.random()亂數Method產生0(含)到7(不含)</h2>

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

<h2>Math.floor()無條件捨去Method</h2>

<p id="demo1"></p>

<h2>Math.ceil()進位Method</h2>

<p id="demo2"></p>

<h2>Math.round()四捨Method</h2>

<p id="demo3"></p>

<script>

let x = Math.random()*7;

document.getElementById("demo").innerHTML = x;

document.getElementById("demo1").innerHTML = Math.floor(x);

document.getElementById("demo2").innerHTML = Math.ceil(x);

document.getElementById("demo3").innerHTML = Math.round(x);

</script>