grapes/Number.lua

local number = {}

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function number.round(num)
    if num >= 0 then
        return math.floor(num + 0.5)
    else
        return math.ceil(num - 0.5)
    end
end

function number.roundToDecimalPlaces(num, decimalPlaces)
    local mult = 10 ^ (decimalPlaces or 0)
    return number.round(num * mult) / mult
end

function number.getDigitCount(num)
    return num == 0 and 1 or math.ceil(math.log(num + 1, 10))
end

function number.shorten(num, digitCount)
    if num < 1000 then
        return num
    else
        local shortcuts = { "K", "M", "G", "T", "P", "E", "Z", "Y" }
        local index = math.floor(math.log(num, 1000))

        return number.roundToDecimalPlaces(num / 1000 ^ index, digitCount) .. shortcuts[index]
    end
end

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return number