有许多四舍五入的方法,例如:
floor 0.8 = 0 and floor (-0.8) = -1ceiling 0.8 = 1 and ceiling (-0.8) = 0truncate 0.8 = 0 and truncate (-0.8) = 0round 0.8 = 1, round (-0.8) = -1, round 0.5 = 0, round 1.5 = 2因此,从你所说的话来看(下23.8 = truncate 23.8 = 23),但询问如果这一数值为负值,你会怎样做。
你的描述似乎表明你想要的是拖拉,而不是四舍五入。 您可使用trunate:
(RealFrac a, Integral b) => a -> b
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