Jump to content

Module:Sortkey: Difference between revisions

From Wikipedia, the free encyclopedia
Content deleted Content added
we can print at most 15 digits, so maximum of 14 on the exponent should avoid rounding errors
mNo edit summary
Line 45: Line 45:
value = value + 10^(mag+1)
value = value + 10^(mag+1)
end
end
sortkey = string.format('%d', prefix) .. string.format('%015.0f', math.floor(value * 10^(math.min(14,14-mag))))
sortkey = string.format('%d', prefix) .. string.format('%015.0f', math.floor(value * 10^(math.min(28,14-mag))))
end
end
return sortkey;
return sortkey;

Revision as of 20:38, 21 September 2018

local getArgs = require('Module:Arguments').getArgs

local p = {}

function p._encode(sortkey)
	-- Protect against sortkey nesting.
	-- Example: {{sort|{{dts|2013|07|07}}|{{dts|1990|12|01}}}}
	if string.find(sortkey, "sortkey") or string.find(sortkey, "data-sort-value") then
		return "";
	end
    return mw.text.encode(sortkey)
end

function p.encode(frame)
	local args = getArgs(frame);
	return p._encode(args[1] or "")
end

local function valid_number(num)
	-- Return true if num is a valid number.
	-- In Scribunto (different from some standard Lua), when expressed as a string,
	-- overflow or other problems are indicated with text like "inf" or "nan"
	-- which are regarded as invalid here (each contains "n").
	if type(num) == 'number' and tostring(num):find('n', 1, true) == nil then
		return true
	end
end

function p._sortKeyForNumber(value)
	if not valid_number(value) then
		if value < 0 then
			sortkey = '1000000000000000000'
		else
			sortkey = '9000000000000000000'
		end
	elseif value == 0 then
		sortkey = '5000000000000000000'
	else
		local mag = math.floor(math.log10(math.abs(value)) + 1e-14)
		local prefix
		if value > 0 then
			prefix = 7000 + mag
		else
			prefix = 2999 - mag
			value = value + 10^(mag+1)
		end
		sortkey = string.format('%d', prefix) .. string.format('%015.0f', math.floor(value * 10^(math.min(28,14-mag))))
	end
	return sortkey;
end

function p.sortKeyForNumber(frame)
	local args = getArgs(frame);
	return p._sortKeyForNumber(args[1] or "")
end

return p