Módulo:Percentagem

--
-- This module implements [[Template:Percentage]]
--
local p = {}

local math_module = require( "Module:Math" )
local precision = math_module._precision
local sortkey = require( "Module:Sortkey" )

local function rnd(num, digits)
    -- This function implements {{rnd}}
    return math_module._precision_format(tostring(num), digits)
end

local function oom(num)
    -- This function implements {{order of magnitude}}
    return math_module._order(tostring(num))
end

function _nonscinote(num)
    -- This function undoes scientific notation
    if mw.ustring.match(num or '', '^%s*(%d)%.(%d+)<span[^<>]*>×</span>10<sup>([%-−]*)(%d)</sup>%s*$') then
        local a,b,c,d = mw.ustring.match(num or '', '^%s*(%d)%.(%d+)<span[^<>]*>×</span>10<sup>([%-−]*)(%d)</sup>%s*$')
        d = tonumber(d) or 1
        if c ~= '' then
            return '0.' .. mw.ustring.rep('0', d - 1) .. a .. b
        else
            return a .. mw.ustring.sub(b .. mw.ustring.rep('0', d ), 1, d)
        end
    end
    return num
end

local function fmtout(num,snote)
    if snote then
        return _nonscinote(num)
    else
        return num
    end
end

function _percentage(n1, n2, prec, suffix, pad, sigfig, sn)
    local pct = 100*n1/n2
    skey = '<span data-sort-value="'
            .. sortkey._sortKeyForNumber(pct) .. '♠" style="display:none"></span>'

    -- prec = math.floor(prec)

    if sigfig ~= '' then
        if pct ~= 0 then
            return skey .. fmtout(rnd(pct, tonumber(sigfig) - oom(pct) - 1), sn) .. suffix
        else
            return skey .. fmtout(rnd(pct, tonumber(sigfig) - 3), sn) .. suffix
        end
    end
    if pad ~= '' then
        return skey .. fmtout(rnd(pct, prec), sn) .. suffix
    end
    
    prec = (prec < 0) and 0 or prec
    if pct ~= 0 then
        pct = ((pct < 0) and -1 or 1)*math.floor(math.abs(pct * 10^prec) + 0.5) / 10^prec
    end
    
    return skey .. fmtout(pct, sn) .. suffix
end

function p.main(frame)
    local args = frame.args[1] and frame.args or frame:getParent().args
    local yesno = require('Module:Yesno')
    return _percentage(
        tonumber(args[1]) or 0,
        tonumber(args[2]) or 100,
        tonumber(args[3]) or tonumber(args['pad']) or 0,
        args['%'] or '%', args['pad'] or '',
        args['sigfig'] or '',
        yesno(args['nonscinote'] or 'no')
        )
end

return p