6.13.3 `ceil', `floor', `rint', `dceil', `dfloor', `drint'
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ceil(NUM)

dceil(NUM)
     :: Get the ceiling integer of NUM.

floor(NUM)

dfloor(NUM)
     :: Get the floor integer of NUM.

rint(NUM)

drint(NUM)
     :: Get the round integer of NUM.

RETURN
     integer

NUM
     number


     [0] dceil(1.1);
     1

