ceil

        # Float.ceil

(from ruby core)
---
    ceil(ndigits = 0) -> float or integer

---

Returns the smallest number greater than or equal to `self` with a
precision of `ndigits` decimal digits.

When `ndigits` is positive, returns a float with `ndigits` digits after
the decimal point (as available):

    f = 12345.6789
    f.ceil(1) # => 12345.7
    f.ceil(3) # => 12345.679
    f = -12345.6789
    f.ceil(1) # => -12345.6
    f.ceil(3) # => -12345.678

When `ndigits` is non-positive, returns an integer with at least
`ndigits.abs` trailing zeros:

    f = 12345.6789
    f.ceil(0)  # => 12346
    f.ceil(-3) # => 13000
    f = -12345.6789
    f.ceil(0)  # => -12345
    f.ceil(-3) # => -12000

Note that the limited precision of floating-point arithmetic may lead to
surprising results:

    (2.1 / 0.7).ceil  #=> 4 (!)

Related: Float#floor.