Floor/Ceil

math_ops.exs

defmodule MathOps do
  def floor(x) when x < 0 do
    t = trunc x
    case x-t == 0 do
      true -> t
      false -> t - 1
    end
  end

  def floor(x) do
    trunc x
  end

  def ceiling(x) when x < 0 do
    trunc x
  end

  def ceiling(x) do
    t = trunc x
    case x-t == 0 do
      true -> t
      false -> t + 1
    end
  end
end