Available inall subroutines.
Computes the smallest integer value greater than or equal to the given value.
In other words, round
x towards positive infinity.
For example, 2.2, 2.5, and 2.7 all ceil to 3.0.
math.NAN, a NaN will be returned.
x is integral, ±0,
x itself is returned.
Otherwise, the rounded value of
x is returned.