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<title>4-03_math</title>
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span {
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<h1>小数第◯位で切り捨てる</h1>
<h2>四則演算以外の計算をする</h2>
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<p>円周率は <span id="pi"></span> です。</p>
<p>ふつうに切り捨てると <span id="floor"></span> です。</p>
<p>小数第2位で切り捨てると <span id="output"></span> です。</p>
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<p>JavaScript Samples</p>
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<script>
'use strict';
document.getElementById('pi').textContent = Math.PI;
document.getElementById('floor').textContent = Math.floor(Math.PI);
function point(num, digit) {
const mover = 10 ** digit;
return Math.floor(num * mover) / mover;
}
document.getElementById('output').textContent = point(Math.PI, 2);
</script>
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KAOKA Daisuke