Module:Convert: Difference between revisions
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>Johnuniq (default rounding done (not checked!); tweaks) |
>Johnuniq (fix table and scaled(); some rounding fixes (more needed...I'll be back)) |
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Line 38: | Line 38: | ||
['K'] = {'temperature', 1, 273.15, 'C'}, | ['K'] = {'temperature', 1, 273.15, 'C'}, | ||
['C'] = {'temperature', 1, 0, 'F'}, | ['C'] = {'temperature', 1, 0, 'F'}, | ||
['F'] = {'temperature', | ['F'] = {'temperature', 5/9, 32, 'C'}, | ||
['°K'] = {'temperature', 1, 273.15, '°C'}, | ['°K'] = {'temperature', 1, 273.15, '°C'}, | ||
['°C'] = {'temperature', 1, 0, '°F'}, | ['°C'] = {'temperature', 1, 0, '°F'}, | ||
['°F'] = {'temperature', | ['°F'] = {'temperature', 5/9, 32, '°C'}, | ||
} | } | ||
-------END DATA TABLE----- | -------END DATA TABLE----- | ||
Line 47: | Line 47: | ||
local function scaled(value, in_unit, out_unit) | local function scaled(value, in_unit, out_unit) | ||
-- Return scaled value for a simple convert. | -- Return scaled value for a simple convert. | ||
return (value - in_unit[units.offset]) | return (value - in_unit[units.offset]) * (in_unit[units.scale] / out_unit[units.scale]) + out_unit[units.offset] | ||
end | end | ||
Line 106: | Line 106: | ||
args.out_unit = out_unit | args.out_unit = out_unit | ||
args.range = range | args.range = range | ||
args.round_to = round_to | args.round_to = args.round_to or round_to -- allow named parameter | ||
return args | return args | ||
end | end | ||
Line 117: | Line 117: | ||
-- if factor >= 0.02, compensate prec by adding N where: | -- if factor >= 0.02, compensate prec by adding N where: | ||
-- N factor is in range | -- N factor is in range | ||
-- 1 | -- 1 .02 : .2 = .1/5 : .1*2 | ||
-- 0 | -- 0 .2 : 2 = 1/5 : 1*2 | ||
-- -1 2 : | -- -1 2 : 20 = 10/5 : 10*2 | ||
-- -2 20 : | -- -2 20 : 200 = 100/5 : 100*2 etc. | ||
-- TODO Exception required for temperature. | -- TODO Exception required for temperature. | ||
prec = 0 | prec = 0 | ||
Line 135: | Line 134: | ||
end | end | ||
if factor ~= nil and factor >= 0.02 then | if factor ~= nil and factor >= 0.02 then | ||
prec = prec - math.floor(factor | prec = prec - math.floor(math.log10(factor*5)) | ||
end | end | ||
return prec | return prec | ||
Line 148: | Line 147: | ||
-- TODO Lots of checking required. Will need tweaks for special cases | -- TODO Lots of checking required. Will need tweaks for special cases | ||
-- handled by old Template:Convert. | -- handled by old Template:Convert. | ||
-- TODO Limit values to avoid abuse (for example, can currently set | |||
-- round_to to very large values like 999). | |||
local text = '' | local text = '' | ||
if invalue == nil then return text end | if invalue == nil then return text end | ||
Line 165: | Line 166: | ||
error(msg:format(parms.sigfig)) | error(msg:format(parms.sigfig)) | ||
end | end | ||
-- TODO %.2g does not do what I fondly remembered. | |||
local fmt = '%.' .. string.format('%.0f', sigfig) .. 'g' | local fmt = '%.' .. string.format('%.0f', sigfig) .. 'g' | ||
text = string.format(fmt, outvalue) | text = string.format(fmt, outvalue) | ||
Line 185: | Line 187: | ||
end | end | ||
if round_to then | if round_to then | ||
if round_to >= 0 then | if round_to >= 0 then | ||
if auto then | |||
-- TODO No less than two significant figures. | |||
end | |||
local fmt = '%.' .. string.format('%.0f', round_to) .. 'f' | local fmt = '%.' .. string.format('%.0f', round_to) .. 'f' | ||
text = string.format(fmt, outvalue) | text = string.format(fmt, outvalue) | ||
else | else | ||
local | -- This always keeps two sig figs. Should that be done if not auto? | ||
local | round_to = -round_to -- #digits that want to zero | ||
text = string.format('% | local maxzeroes = 0 -- maximum #digits that should be zeroed | ||
if outvalue > 100 then | |||
maxzeroes = math.log10(outvalue) - 1 | |||
end | |||
if round_to > maxzeroes then | |||
round_to = maxzeroes | |||
end | |||
if round_to > 0 then | |||
local scaled = string.format('%.0f', outvalue/(10^round_to)) | |||
text = scaled .. string.rep('0', round_to) | |||
else | |||
-- TODO Not satisfactory? Should limit sigfigs? | |||
text = string.format('%f', outvalue) | |||
end | |||
end | end | ||
end | end |
Revision as of 03:54, 6 September 2012
Documentation for this module may be created at Module:Convert/doc
--[[ TODO Too many items to list, but following are some points: - Output needs rather than space in several places. - Some conversions require two outputs: {{convert|55|nmi|km mi}}. - Some units have two values: {{convert|3.21|m|ftin}}. ]]-- --[[-----BEGIN DATA TABLE----- Plan to write a program to generate the conversion tables below. The input would be a text file in human-friendly format, and the output would be the following tables. When a lot of data is added, it might be useful to put this in another module. Values from http://en.wikipedia.org/wiki/Conversion_of_units Check with http://en.wikipedia.org/wiki/Template:Convert/list_of_units ]]-- local units = { -- Each value is {converter_table, default_out_unit}. lookup = function (self, unit) -- If unit is known, return its converter_table, default_out_unit. local t = self[unit] if t == nil then local msg = 'Unit %s not known[[Category:Convert unknown unit]]' error(msg:format(unit)) end return t end, utype = 1, scale = 2, offset = 3, defaultunit = 4, ['kg'] = {'mass', 1, 0, 'lb'}, ['lb'] = {'mass', 0.45359237, 0, 'kg'}, ['m'] = {'length', 1, 0, 'ft'}, ['km'] = {'length', 1000, 0, 'mi'}, ['mi'] = {'length', 1609.344, 0, 'km'}, ['ft'] = {'length', 0.3048, 0, 'm'}, ['K'] = {'temperature', 1, 273.15, 'C'}, ['C'] = {'temperature', 1, 0, 'F'}, ['F'] = {'temperature', 5/9, 32, 'C'}, ['°K'] = {'temperature', 1, 273.15, '°C'}, ['°C'] = {'temperature', 1, 0, '°F'}, ['°F'] = {'temperature', 5/9, 32, '°C'}, } -------END DATA TABLE----- local function scaled(value, in_unit, out_unit) -- Return scaled value for a simple convert. return (value - in_unit[units.offset]) * (in_unit[units.scale] / out_unit[units.scale]) + out_unit[units.offset] end local function require_number(value, missing, invalid) -- If value is missing or not a number, throw an error. -- Return value as a number if valid. if value == nil then error(missing) end local number = tonumber(value) if number == nil then error(invalid:format(value)) end return number end local function require_integer(value, missing, invalid) -- If value is missing or not an integer, throw an error. -- Return value as a number if valid. local number = require_number(value, missing, invalid) if number ~= math.floor(number) then error(invalid:format(value)) end return number end local function get_parms(pframe) -- Return table with all arguments passed by template converted to -- named arguments. The numeric args are used to add named args: -- in_text, in_text2 (strings given for value, value2) -- value, in_unit, out_unit, value2, range, round_to -- (except for range, which is nil or a table, the named args that are -- added here could be provided by the user of the template). local range_types = { -- text to separate input, output ranges ['and'] = {' and ', ' and '}, ['by'] = {' by ', ' by '}, ['to'] = {' to ', ' to '}, ['-'] = {'–', '–'}, ['to(-)'] = {' to ', '–'}, ['x'] = {' by ', ' × '}, ['+/-'] = {' ± ', ' ± '}, } local args = {} -- arguments passed to template for k,v in pframe:argumentPairs() do args[k] = v end args.in_text = args[1] args.value = require_number(args.in_text, 'Need value', 'Value "%s" must be a number') local in_unit = args[2] local i = 3 local range = range_types[in_unit] if range ~= nil then args.in_text2 = args[3] args.value2 = require_number(args.in_text2, 'Need second value', 'Second value "%s" must be a number') in_unit = args[4] i = 5 end local out_unit = args[i] local round_to = args[i+1] if in_unit == nil then error('Need input unit') end args.in_unit = in_unit args.out_unit = out_unit args.range = range args.round_to = args.round_to or round_to -- allow named parameter return args end local function default_roundto(intext, factor) -- Return a default value for round_to (an integer like 2, 0, -2). -- prec = (precision implied in intext) -- = (#digits after dot, or negative of #zeroes before dot) -- If conversion is multiplication by a factor, and -- if factor >= 0.02, compensate prec by adding N where: -- N factor is in range -- 1 .02 : .2 = .1/5 : .1*2 -- 0 .2 : 2 = 1/5 : 1*2 -- -1 2 : 20 = 10/5 : 10*2 -- -2 20 : 200 = 100/5 : 100*2 etc. -- TODO Exception required for temperature. prec = 0 dot = intext:find('.', 1, true) if dot ~= nil then prec = intext:sub(dot+1):len() if prec == 0 then intext = intext:sub(1, -2) end end if prec == 0 then prec = -intext:match('0*$'):len() end if factor ~= nil and factor >= 0.02 then prec = prec - math.floor(math.log10(factor*5)) end return prec end local function cvtround(invalue, intext, parms) -- Convert given invalue using parms (return '' if invalue == nil). -- Return rounded, formatted string for result, using rounding -- specified in parms. -- This code combines convert/round because some rounding requires -- knowledge of what we are converting. -- TODO Lots of checking required. Will need tweaks for special cases -- handled by old Template:Convert. -- TODO Limit values to avoid abuse (for example, can currently set -- round_to to very large values like 999). local text = '' if invalue == nil then return text end local outvalue = scaled(invalue, parms.in_unit_table, parms.out_unit_table) local round_to = parms.round_to local sigfig = parms.sigfig local disp = parms.disp local auto = false if round_to then -- Ignore sigfig, disp. round_to = require_integer(round_to, 'Need value', 'round_to "%s" must be an integer') elseif sigfig then -- Ignore disp. sigfig = require_integer(sigfig, 'Need value', 'sigfig "%s" must be an integer') if sigfig <= 0 then msg = 'sigfig "%s" must be positive' error(msg:format(parms.sigfig)) end -- TODO %.2g does not do what I fondly remembered. local fmt = '%.' .. string.format('%.0f', sigfig) .. 'g' text = string.format(fmt, outvalue) elseif disp == '5' then local negative = false if outvalue < 0 then negative = true outvalue = -outvalue end outvalue = math.floor((outvalue / 5) + 0.5) * 5 if negative then outvalue = -outvalue end text = string.format('%.0f', outvalue) else auto = true -- using default rounding -- TODO If conversion is not multiplication by a number, need factor = nil. local factor = outvalue / invalue round_to = default_roundto(intext, factor) end if round_to then if round_to >= 0 then if auto then -- TODO No less than two significant figures. end local fmt = '%.' .. string.format('%.0f', round_to) .. 'f' text = string.format(fmt, outvalue) else -- This always keeps two sig figs. Should that be done if not auto? round_to = -round_to -- #digits that want to zero local maxzeroes = 0 -- maximum #digits that should be zeroed if outvalue > 100 then maxzeroes = math.log10(outvalue) - 1 end if round_to > maxzeroes then round_to = maxzeroes end if round_to > 0 then local scaled = string.format('%.0f', outvalue/(10^round_to)) text = scaled .. string.rep('0', round_to) else -- TODO Not satisfactory? Should limit sigfigs? text = string.format('%f', outvalue) end end end return text end local disp_single = { ['or'] = '%s %s or %s %s', ['sqbr'] = '%s %s [%s %s]', ['comma'] = '%s %s, %s %s', ['b'] = '%s %s (%s %s)', } local disp_double = { ['or'] = '%s%s%s %s or %s%s%s %s', ['sqbr'] = '%s%s%s %s [%s%s%s %s]', ['comma'] = '%s%s%s %s, %s%s%s %s', ['b'] = '%s%s%s %s (%s%s%s %s)', } local function process(parms) -- If we can convert from given in to out unit, return the table values for the two given unit types. parms.in_unit_table = units:lookup(parms.in_unit) if parms.out_unit == nil then -- need to catch empty string also? parms.out_unit = parms.in_unit_table[units.defaultunit] end parms.out_unit_table = units:lookup(parms.out_unit) if parms.in_unit_table[units.utype] ~= parms.out_unit_table[units.utype] then local msg = 'Cannot convert %s to %s' error(msg:format(parms.in_unit_table[units.utype], parms.out_unit_table[units.utype])) end local intext = parms.in_text local intext2 = parms.in_text2 local outext = cvtround(parms.value, intext, parms) local outext2 = cvtround(parms.value2, intext2, parms) local range = parms.range local disp = parms.disp local wikitext if range == nil then wikitext = disp_single[disp] or disp_single['b'] wikitext = wikitext:format(intext, parms.in_unit, outext, parms.out_unit) else wikitext = disp_double[disp] or disp_double['b'] wikitext = wikitext:format(intext, range[1], intext2, parms.in_unit, outext, range[2], outext2, parms.out_unit) end return wikitext end -- Used by template {{convert2}}. -- We will have to keep old {{convert}} for a long time, and run -- {{convert2}} in parallel with {{convert}} while testing/developing. local p = {} local bodge = require "Module:mw" -- This fixes up mw.text.tag for us. function p.convert(frame) local pframe = frame:getParent() local parms = get_parms(pframe) local state,text = pcall(process, parms) if not state then local params = {style="color:black; background-color:orange;"} text=mw.text.tag({name="span", contents="[[Module talk:Convert|Conversion error]]: " .. text, params=params}) end return text end return p