floor rounding by rounding method Syntax format: float floor (float value)
Returns the next integer not greater than value, and rounds the decimal part of value. 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 rounding 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. 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); >echo round(1241757, -3); // 1242000
echo round(5.045, 2); // 5.05
echo round(5.055, 2); // 5.06
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