local roman_dict = {M = 1000, D = 500, C = 100, L = 50, X = 10, V = 5, I = 1}
local repeatable = {M = true, C = true, X = true, I = true}
local roman_table = {'M', 'CM', 'D', 'CD', 'C', 'XC', 'L', 'XL', 'X', 'IX', 'V', 'IV', 'I'}
local arabic_table = {1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1 }
local export = {}
local function nil_or_error(msg, no_error)
if no_error then
return nil
else
error(msg, 2)
end
end
function export.arabic_to_roman(arabic, no_error, to_lower, use_j, use_iiii)
if arabic == '' or arabic == nil then return nil end
arabic = mw.ustring.gsub(arabic, ",", "")
local j = tonumber(arabic)
if j == nil then return nil end
if j <= 0 or j > 3999 then
return nil_or_error("Out of valid range", no_error)
end
local result = {}
local a, count
for i, r in ipairs(roman_table) do
a = arabic_table[i]
count = math.floor(j / a)
table.insert(result, string.rep(r, count))
j = j % a
if j <= 0 then break end
end
local out = table.concat(result)
if to_lower then out = mw.ustring.lower(out) end
if use_iiii and out:sub(-2, -1) == "IV" then out = out:sub(1, -3) .. "IIII" end
if use_iiii and out:sub(-2, -1) == "iv" then out = out:sub(1, -3) .. "iiii" end
if use_j and out:sub(-1, -1) == "I" then out = out:sub(1, -2) .. "J" end
if use_j and out:sub(-1, -1) == "i" then out = out:sub(1, -2) .. "j" end
return out
end
function export.roman_to_arabic(roman, no_error)
if roman == '' or roman == nil then
return nil
else
roman = mw.ustring.upper(roman):gsub("J", "I")
end
if not mw.ustring.match(roman, "^[MDCLXVI]+$") then
return nil_or_error("Illegal Roman numeral format", no_error)
end
local result = 0
local i = 1
local s1, s2, c2
local length = #roman
while i <= length do
s1 = roman_dict[roman:sub(i, i)]
if s1 == nil then
return nil_or_error("Unrecognized character in input", no_error)
elseif (i + 1) <= length then
c2 = roman:sub(i + 1, i + 1)
s2 = roman_dict[c2]
if s2 == nil then
return nil_or_error("Unrecognized character in input", no_error)
elseif s1 >= s2 then
if s1 == s2 and not repeatable[c2] then
return nil_or_error("Illegal Roman numeral format: “" .. c2 .. "” may not appear adjacent to itself", no_error)
end
result = result + s1
else
result = result + s2 - s1
i = i + 1
end
else
result = result + s1
end
i = i + 1
end
return result
end
function export.roman_to_arabic_t(frame)
local params = {
[1] = {},
['no_error'] = {type = 'boolean'},
}
local args = require("Module:parameters").process(frame:getParent().args, params)
return export.roman_to_arabic(args[1], args.no_error)
end
function export.arabic_to_roman_t(frame)
local params = {
[1] = {},
['lower'] = {type = 'boolean'},
['j'] = {type = 'boolean'},
['iiii'] = {type = 'boolean'},
['no_error'] = {type = 'boolean'},
}
local args = require("Module:parameters").process(frame:getParent().args, params)
return export.arabic_to_roman(args[1], args.no_error, args.lower, args.j, args.iiii)
end
return export