How to round PHP to one decimal place?

In PHP, you can use the round() function to round off a number and keep one decimal place. The usage of the function is as follows:

$number = 15.6789;
$roundedNumber = round($number, 1);
echo $roundedNumber; // 输出 15.7

In the example above, the variable $number holds a number with multiple decimal places. By calling the round() function and passing the number as the first parameter, while also passing the desired number of decimal places to be retained as the second parameter, you can get the result rounded to one decimal place.