Round each number in interval X towards +Inf.
Accuracy: The result is a tight enclosure.
ceil (infsup (2.5, 3.5)) ⇒ ans = [3, 4] ceil (infsup (-0.5, 5)) ⇒ ans = [0, 5]
See also: @infsup/floor, @infsup/round, @infsup/roundb, @infsup/fix.
Package: interval