PHP圓整到5小數

Question

預期函數簽名的先前多個：

function roundToPreviousMultipleWithDecimal(float $number, int $x = 5): float; 

• 8.4 => 8.0
• 8.6 => 8.5
• 8.9 => 8.5
• 9.0 => 9.0

Answer 1

一個簡單的解決方案，地板的雙數和除以二... 2美分;）

<?php 

function roundToPreviousMultipleWithDecimal(float $number){ 

     return $specificRound = floor($number * 2)/2; 
} 

$a = 8.4; 
$b = 8.6; 
$c = 8.9; 
$d = 9.0; 

echo roundToPreviousMultipleWithDecimal($a) ."<br />"; 
echo roundToPreviousMultipleWithDecimal($b) ."<br />"; 
echo roundToPreviousMultipleWithDecimal($c) ."<br />"; 
echo roundToPreviousMultipleWithDecimal($d) ."<br />";