Module:FormatNum
Documentation for this module may be created at Module:FormatNum/doc
local FormatNum = { suite = "FormatNum",
serial = "2016-11-25" };
--[[
FormatNum
* format
* minus
* padding
* roman2number
* round
* failsafe
FormatNum()
]]
local DEFAULT_FORMAT = "dewiki";
local DEFAULT_METHOD = 0;
-- Constant for round method "round half to even" (IEEE 754)
local ROUND_TO_EVEN = 0;
-- Constant for round method "round half away from zero"
-- (German: "kaufmaennisches Runden"),
-- also filters "-0" and converts it to "0".
local ROUND_AWAY_FROM_ZERO = 1;
-- Constant for U+202F
local THIN_SPACE = mw.ustring.char( 8239 );
-- Constant for reducing code range to ANSI
local SPACER_SPAN = "<span style='width:.25em'> </span>";
-- Constant for padding span element
local PADDING_SPAN = "<span style='visibility:hidden'>%s%s</span>";
-- Table storing the format options.
local FORMAT_TABLE = {
dewiki = {
decimalMark = ",",
groupMark = ".",
groupMinLength = 4,
groupNaturalLength = 5,
groupOnlyIntegerPart = false
},
dewikiint = {
decimalMark = ",",
groupMark = THIN_SPACE,
groupMinLength = 4,
groupNaturalLength = 5,
groupOnlyIntegerPart = true
},
de = {
decimalMark = ",",
groupMark = THIN_SPACE,
groupMinLength = 4,
groupNaturalLength = 4,
groupOnlyIntegerPart = false
},
de_currency = {
decimalMark = ",",
groupMark = ".",
groupMinLength = 4,
groupNaturalLength = 4,
groupOnlyIntegerPart = false
},
ch = {
decimalMark = ",",
groupMark = "'",
groupMinLength = 5,
groupNaturalLength = 5,
groupOnlyIntegerPart = true
},
en = {
decimalMark = ".",
groupMark = ",",
groupMinLength = 4,
groupNaturalLength = 4,
groupOnlyIntegerPart = true
},
iso31_0 = { -- ISO 31-0 using comma as decimal mark
decimalMark = ",",
groupMark = THIN_SPACE,
groupMinLength = 4,
groupNaturalLength = 4,
groupOnlyIntegerPart = false
},
iso31_0_point = { -- ISO 31-0 using dot as decimal mark
decimalMark = ".",
groupMark = THIN_SPACE,
groupMinLength = 4,
groupNaturalLength = 4,
groupOnlyIntegerPart = false
},
comma = {
decimalMark = ",",
groupMark = "",
groupMinLength = 1000, -- (for performance, but also small values wouldn't matter)
groupNaturalLength = 1000,
groupOnlyIntegerPart = true
},
pc = nil -- prevent formatting
};
-- Format table for "at" (only for convenience, same as "iso31_0").
FORMAT_TABLE.at = FORMAT_TABLE.iso31_0;
-- Format table for "ch_currency" (only for convenience, same as "dewiki").
FORMAT_TABLE.ch_currency = FORMAT_TABLE.dewiki;
-- Constant defining digit group lengths when digit grouping is used.
local DIGIT_GROUPING_SIZE = 3;
-- Table defining roman digit values.
local ROMAN_DIGITS = { I = 1,
V = 5,
X = 10,
L = 50,
C = 100,
D = 500,
M = 1000 };
--[[
Internal used function for rounding.
@param a_number : Number to be rounded.
@param a_precision : Number of significant digits of the fractional part. If it
is negative, the according number of digits of the integer part are also
rounded.
@param a_roundMethod : Numeric constant defining the round method to use.
Supported are ROUND_TO_EVEN and ROUND_AWAY_FROM_ZERO.
@return String of the rounded number like returned by Lua function string.format().
]]
local function numberToString( a_number, a_precision, a_roundMethod )
local suitable;
if (a_precision < 0) then
a_precision = -a_precision;
if (a_roundMethod == ROUND_TO_EVEN) then
local integerPart = math.floor(math.abs(a_number) / (10 ^ a_precision));
if (integerPart % 2 == 0) then
-- next even number smaller than a_number / 10^precision
a_number = a_number - 5 * (10 ^ (a_precision - 1));
a_number = math.ceil(a_number / (10 ^ a_precision)) * (10 ^ a_precision);
else
-- next even number bigger than a_number / 10^precision
a_number = a_number + 5 * (10 ^ (a_precision - 1));
a_number = math.floor(a_number / (10 ^ a_precision)) * (10 ^ a_precision);
end
elseif (a_roundMethod == ROUND_AWAY_FROM_ZERO) then
if (a_number >= 0) then
a_number = a_number + 5 * (10 ^ (a_precision - 1));
a_number = math.floor(a_number / (10 ^ a_precision)) * (10 ^ a_precision);
else
a_number = a_number - 5 * (10 ^ (a_precision - 1));
a_number = math.ceil(a_number / (10 ^ a_precision)) * (10 ^ a_precision);
end
end
-- handle it as normal integer
a_precision = 0;
end
if (a_roundMethod == ROUND_AWAY_FROM_ZERO) then
if ((a_number * (10 ^ a_precision)) - math.floor(a_number * (10 ^ a_precision)) == 0.5) then
-- because string.format() uses round to even, we have to add (numbers >0) or
-- subtract (numbers <0) a little bit to point into the "correct" rounding
-- direction if a_number is exactly in the middle between two rounded numbers
if (a_number >= 0) then
a_number = a_number + (10 ^ -(a_precision + 1));
else
a_number = a_number - (10 ^ -(a_precision + 1));
end
else
if (math.abs(a_number * (10 ^ a_precision)) < 0.5) then
-- filter "-0" and convert it to 0
a_number = math.abs(a_number);
end
end
end
suitable = string.format( "%%.%df", a_precision )
return string.format( suitable, a_number );
end -- numberToString()
--[[
Internal used for formatting.
@param a_number : String (ASCII) of a non-negative number to be formatted.
@param a_sign : String with a sign char, or false
@param a_decimalMark : String of the decimal mark to use.
@param a_groupMark : String of the mark used for digit grouping.
@param a_groupMinLength : Number defining the minimum length of integer part
to use digit grouping (normally 4 or 5). However if fractional part is
longer than DIGIT_GROUPING_SIZE (3 as default) and digit grouping of
fractional part is not disabled via 'a_groupOnlyIntegerPart', then this
value is ignored and set to DIGIT_GROUPING_SIZE + 1.
@param a_groupNaturalLength : a_groupMinLength for unsigned integer; or nil
@param a_groupOnlyIntegerPart : Boolean defining whether activating digit
grouping only for integer part (true) or for integer and fractional part
(false).
@return String of the formatted number according to the parameters.
]]
local function formatNumber( a_number,
a_sign,
a_decimalMark,
a_groupMark,
a_groupMinLength,
a_groupNaturalLength,
a_groupOnlyIntegerPart )
-- find the decimal point
local decimalPosition = a_number:find(".", 1, true);
local needsGrouping = false;
if not decimalPosition then
-- no decimal point - integer number
local minLength = a_groupMinLength;
if not a_sign and a_groupNaturalLength then
minLength = a_groupNaturalLength;
end
decimalPosition = #a_number + 1;
if decimalPosition > minLength then
needsGrouping = true;
end
else
-- decimal point present
if decimalPosition > a_groupMinLength
or (#a_number - decimalPosition > DIGIT_GROUPING_SIZE
and not a_groupOnlyIntegerPart) then
needsGrouping = true;
end
-- replace the decimal point
a_number = a_number:sub( 1, decimalPosition - 1 )
.. a_decimalMark
.. a_number:sub( decimalPosition + 1 );
end
if needsGrouping and decimalPosition > DIGIT_GROUPING_SIZE + 1 then
-- grouping of integer part necessary
local i = decimalPosition - DIGIT_GROUPING_SIZE;
while (i > 1) do
-- group the integer part
a_number = a_number:sub( 1, i - 1 )
.. a_groupMark
.. a_number:sub( i );
decimalPosition = decimalPosition + #a_groupMark;
i = i - DIGIT_GROUPING_SIZE;
end
end
-- skip to the end of the new decimal mark (in case it is more than one char)
decimalPosition = decimalPosition + #a_decimalMark - 1;
if a_groupOnlyIntegerPart then
needsGrouping = false;
end
if needsGrouping and #a_number - decimalPosition > DIGIT_GROUPING_SIZE then
-- grouping of fractional part necessary
-- using negative numbers (index from the end of the string)
local i = decimalPosition - #a_number + DIGIT_GROUPING_SIZE;
while i < 0 do
-- group the fractional part
a_number = a_number:sub(1, i - 1) .. a_groupMark .. a_number:sub(i);
i = i + DIGIT_GROUPING_SIZE;
end
end
if (a_sign) then
a_number = a_sign .. a_number;
end
return a_number;
end -- formatNumber()
--[[
Formatting numbers.
@param source : Numerical or string representation
of an unformatted (but maybe rounded) floating point or integer number.
@param spec : Formatting option. Currently there are
"at", "comma", "de", "dewiki", "de_currency", "ch", "ch_currency", "en",
"iso31_0", "iso31_0_point" and "pc" supported.
Defaults to "dewiki".
See the FORMAT_TABLE for details.
@param meet : HTML padding on left or right end.
Defaults to 'none' or 0.
Positive figures require padding behind decimal mark,
negative values ensure at least that absolute value
of characters before decimal mark.
@return String of the formatted number.
If the argument 'spec' is invalid
or 'source' is not a valid string representation of a number,
'source' is returned unmodified.
]]
FormatNum.format = function ( source, spec, meet )
local stitch = type( source );
local r;
if stitch == "string" then
r = mw.text.trim( source );
if r == "" then
r = false;
end
elseif stitch == "number" then
r = tostring( source );
end
if r then
if not spec then
spec = DEFAULT_FORMAT;
end
local format = FORMAT_TABLE[ spec ];
if format then
-- format entry found
local sign = mw.ustring.sub( r, 1, 1 );
local scan = mw.ustring.format( "^[%%+%%-%c]", 8722 );
local last;
if mw.ustring.match( sign, scan ) then
-- remove sign from r, add it again later
r = mw.ustring.sub( r, 2 );
else
-- was not a sign
sign = false;
end
if r:sub( 1, 1 ) == "." then
-- r begins with "." -> add a 0 to the beginning
r = "0" .. r;
elseif r:sub( -1 ) == "." then
-- r ends with "." -> remove it
r = r:sub( 1, -2 );
last = true;
end
if r == r:match( "^%d+$" ) or
r == r:match( "^%d+%.%d+$" ) then
-- r has valid format (only digits or digits.digits)
r = formatNumber( r, sign,
format.decimalMark,
format.groupMark,
format.groupMinLength,
format.groupNaturalLength,
format.groupOnlyIntegerPart );
if meet then
local stop;
if not last then
stop = format.decimalMark;
end
r = FormatNum.padding( r, meet, stop );
end
if format.groupMark == THIN_SPACE and SPACER_SPAN then
r = mw.ustring.gsub( r, THIN_SPACE, SPACER_SPAN );
end
else
-- r has no valid format -> undo all modifications
r = source;
end
end
end
return r;
end -- FormatNum.format()
--[[
Convert possible Unicode minus U+2212 into ASCII hyphen-minus.
@param source : String representation of a number.
@param larger : nil/false = Unicode -> ASCII.
@return String with one Unicode minus replaced by ASCII hyphen-minus.
]]
FormatNum.minus = function ( source, larger )
local r = mw.ustring.char( 8722 );
if larger then
r = source:gsub( "-", r, 1 );
else
r = mw.ustring.gsub( source, r, "-", 1 );
end
-- gsub has two results.
return r;
end -- FormatNum.minus()
--[[
HTML padding of number strings.
@param number : string with floating point or integer number
@param meet : Positive figures require padding behind decimal mark,
negative values ensure at least that absolute value
of characters before decimal mark.
Defaults to 'none' or 0.
@param stop : string with decimal mark; if false: number is integer.
@return String of the formatted number.
]]
FormatNum.padding = function ( number, meet, stop )
local r = number;
if type( number ) == "string" and
type( meet ) == "number" and
( not stop or
( type( stop ) == "string" and
stop:match( "^%p$" ) ) ) then
local m = math.floor( meet );
if m ~= 0 then
local i, s;
r = mw.text.trim( r );
if stop then
i = r:find( stop, 1, true );
s = "";
else
i = mw.ustring.len( r );
s = ".";
end
if i then
local left = ( m < 0 );
local n = m + i;
if left then
n = 1 - n;
else
n = n - mw.ustring.len( r );
end
if n > 0 then
s = string.format( PADDING_SPAN,
s,
string.rep( "0", n ) );
if left then
r = s .. r;
else
r = r .. s;
end
end
end
end
end
return r;
end -- FormatNum.padding()
--[[
Convert string of roman digits into number.
@param roman : string with roman number, case-insensitive,
and possibly trailing suffix.
@param suffix : nil, or string with pattern for permitted suffix.
@return
1. Read number, or false if error.
2. nil, or string with detected trailing suffix.
]]
FormatNum.roman2number = function ( roman, suffix )
local d = mw.text.split( roman, "" );
local n = #d;
local r = 0;
local r2 = false;
local k;
for i = 1, n do
k = ROMAN_DIGITS[ d[ i ]:upper() ];
if k then
d[ i ] = k;
else
r2 = table.concat( d, "", i );
if suffix and mw.ustring.match( r2, "^" .. suffix ) then
n = i - 1;
else
r = false;
end
break; -- for i
end
end -- for i
if r then
local j = 0;
local l = true;
for i = n, 1, -1 do
k = d[ i ];
if k > j then
r = r + k;
l = true;
elseif k < j then
r = r - k;
l = false;
elseif l then
r = r + k;
else
r = r - k;
end
j = k;
end -- for i
end
return r, r2;
end -- FormatNum.roman2number()
--[[
Rounding numbers.
@param number : string with unformatted floating point or integer number, or number.
@param precision : number of significant fractional part digits.
If precision is negative, the integer part is rounded as well.
@param method : number defining the rounding method to use.
Currently are supported only
0 for 'IEEE 754' rounding (default) and
1 for 'round half away from zero'.
If another number is supplied, the result is undefined.
@param lone : boolean or nil; omit decimal separator
on floating point numbers without triling digits.
@return String of the rounded number as returned by Lua function string.format().
]]
FormatNum.round = function ( source, precision, method, lone )
local n = math.floor( precision );
local r;
if n then
local stitch = type( source );
local lower;
if stitch == "string" then
r = mw.text.trim( source );
if r == "" then
r = false;
elseif n > 0 then
local s = r:match( "^-?%d+%.(%d+)$" );
if not s or #s < n then
n = false;
end
else
lower = r:find( ".", 1, true ) and not lone;
end
if r and n then
r = tonumber( r );
end
elseif stitch == "number" then
r = source;
end
if r and n then
local m;
if type( method ) == "number" then
m = math.floor( method );
else
m = DEFAULT_METHOD;
end
r = numberToString( r, n, m );
if lower then
r = r .. ".";
end
end
end
return r or source;
end -- FormatNum.round()
--[[
Retrieve versioning and check for compliance.
@param assert : string with with required version, or false.
@return String with appropriate version, or false.
]]
FormatNum.failsafe = function ( assert )
local r;
if assert and assert > FormatNum.serial then
r = false;
else
r = FormatNum.serial;
end
return r;
end -- FormatNum.failsafe()
local p = { };
p.format = function ( frame )
-- @param 1 : unformatted (but maybe rounded) floating point or integer number.
-- @param 2 : Formatting option. Currently there are supported:
-- "at", "comma", "de", "dewiki", "de_currency", "ch",
-- "ch_currency", "en", "iso31_0", "iso31_0_point" and "pc".
local source = frame.args[ 1 ];
local spec = frame.args[ 2 ];
if spec then
spec = mw.text.trim( spec );
if spec == "" then
spec = false;
end
end
return FormatNum.format( source, spec ) or "";
end -- .format()
p.minus = function ( frame )
-- @param 1 : number, with possible Unicode minus or vice versa.
-- @param 2 : boolean, turning ASCII hyphen into Unicode minus.
local larger = frame.args[ 2 ];
if larger then
larger = mw.text.trim( larger );
if larger == "" or larger == "0" then
larger = false;
end
end
return FormatNum.minus( frame.args[ 1 ], larger );
end -- .minus()
p.padding = function ( frame )
-- @param 1 : number to be padded
-- @param 2 : number of trailing or leading figures for alignment
-- @param 3 : string with decimal mark
local r = frame.args[ 1 ];
local meet = tonumber( frame.args[ 2 ] );
local stop = frame.args[ 3 ];
if r and meet and stop then
stop = mw.text.trim( stop );
r = FormatNum.padding( r, meet, stop );
else
r = r or "";
end
return r;
end -- .padding()
p.roman2number = function ( frame )
-- @param 1 : roman number, possibly with trailing suffix
-- @param 2 : pattern for permitted suffix, or not
local r = frame.args[ 1 ];
if r then
local suffix = frame.args[ 2 ];
r = mw.text.trim( r );
if #r > 0 then
if suffix then
suffix = mw.text.trim( suffix );
if #suffix == 0 then
suffix = false;
end
end
r = FormatNum.roman2number( r, suffix )
end
end
return r or "";
end -- .roman2number()
p.round = function ( frame )
-- @param 1 : unformatted floating point or integer number.
-- @param 2 : precision; number of significant fractional part digits.
-- If precision is negative, the integer part is rounded as well.
-- @param method : number defining the rounding method to be used.
-- Currently are supported only
-- 0 for 'IEEE 754' rounding (default) and
-- 1 for 'round half away from zero'.
-- If another number is supplied, the result is undefined.
-- @param format : trigger formatting, if set to a formatting option.
-- @param padding : trigger formatting and padding, if set to a number.
local r = frame.args[ 1 ];
local precision = tonumber( frame.args[ 2 ] );
if r and precision then
local suitable = frame.args.format;
local meet = tonumber( frame.args.padding );
local method = tonumber( frame.args.method );
local int = frame.args[ 2 ]:find( "-0", 1, true );
r = FormatNum.round( r, precision, method, int );
if suitable then
suitable = mw.text.trim( suitable );
if #suitable == 0 then
suitable = false;
end
end
if suitable or meet then
r = FormatNum.format( r, suitable, meet );
end
else
r = r or "";
end
return r;
end -- .round()
p.failsafe = function ( frame )
-- Retrieve versioning and check for compliance.
-- @param 1 : string with with required version, or empty.
-- @return String with appropriate version, or false.
local s = type( frame );
local since;
if s == "table" then
since = frame.args[ 1 ];
elseif s == "string" then
since = frame;
end
if since then
since = mw.text.trim( since );
if #since == 0 then
since = false;
end
end
return FormatNum.failsafe( since ) or "";
end
-- Export access for Lua modules
p.FormatNum = function ()
return FormatNum;
end -- .FormatNum()
return p;