Several methods of rounding in php_PHP tutorial

floor rounding syntax format: float floor (float value)
Returns the next integer not greater than value, rounding off the decimal part of value all. The type returned by floor() is still float, because the range of float values ​​is usually larger than that of integer.
echo floor(4.3); // 4
echo floor(9.999); // 9

ceil is rounded to the nearest integer. Syntax format: float ceil (float value)
Returns the next integer that is not less than value. If value has a decimal part, it is rounded up by one digit. The type returned by ceil() is still float, because the range of float values ​​is usually larger than that of integer
echo ceil(4.3); // 5
echo ceil(9.999); // 10

round rounds floating point numbers
Syntax: float round ( float val [, int precision] )
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
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