Differences in usage of php rounding functions ceil, floor, round, intval

echo ceil(4.3); // 5
echo ceil(9.999); // 10
?>

2. floor — rounding by rounding illustrate float floor ( float $value ) Returns the next integer not greater than value, with the decimal part of value rounded off. The type returned by floor() is still float because the range of float values ​​is usually larger than that of integer. floor() example

echo floor(4.3); // 4
echo floor(9.999); // 9
?>

3, round — perform floating point numbers rounding illustrate float round ( float $val [, int $precision ] ) Returns val rounded to the specified precision (the number of decimal digits after the decimal point). precision can also be negative or zero (default). round() example

echo round(3.4); // 3
echo round(3.5); // 4
echo round(3.6); // 4
echo round(3.6, 0); / / 4
echo round(1.95583, 2); // 1.96
echo round(1241757, -3); // 1242000
echo round(5.045, 2); // 5.05
echo round(5.055, 2); // 5.06
?>

Note: PHP cannot handle strings like "12,300.2" correctly by default. Note: The precision parameter was introduced in PHP 4.

4. intval — Get the integer value of the variable illustrate int intval ( mixed $var [, int $base ] ) Returns the integer value of variable var using a specific base conversion (default is decimal). var can be any scalar type. intval() cannot be used with arrays or objects. intval() example

echo intval(4.3); // 4
echo intval(9.999); // 9
?>

Instructions: The base argument to intval() has no effect unless the var argument is a string.

Summary: The floor function has the same function as the intval function. The difference is that one returns a floating point number (float) and the other is an integer (integer), because the range of float values ​​is usually larger than that of integer. But as far as the numerical value itself is concerned Both are equal.