PHP四舍五入精确小数位及取整方法

<p>$num=0.0215489;</p><p>echo sprintf("%.3f", $num); // 0.022</p><p><span>立即学习</span>“<a href="https://pan.quark.cn/s/7fc7563c4182" style="text-decoration: underline !important; color: blue; font-weight: bolder;" rel="nofollow" target="_blank">PHP免费学习笔记（深入）</a>”；</p>

<p>$num=0.0215489;</p><p>echo substr(sprintf("%.4f", $num),0,-1); // 0.021</p>
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<p>echo ceil(4.3);    // 5</p><p>echo ceil(9.999);  // 10</p>

<p>echo floor(4.3);   // 4</p>echo floor(9.999); // 9