Several ways to parse PHP _php skills

Floor the whole grammar format: float floor (float value)
Returns the next integer not more than value, rounding out the decimal part of value. The type returned by floor () is still float, because the float value is usually larger than the integer.
echo floor (4.3); 4
echo Floor (9.999); 9

ceil Grammar format: float ceil (float value)
Returns the next integer that is not less than value, or the value if there is a decimal part. The type returned by Ceil () is still float, because the float value is usually larger than the integer
echo ceil (4.3); 5
echo ceil (9.999); 10

round the 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