Module:Gapnum

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This module is used by {{val}}.

Use in other modules

gaps

The gaps function can be useful for formatting in other modules that work with displaying large numbers.

local gaps = require('Module:Gapnum').gaps

Using the gaps function, the first argument is the number to format. The second argument can be a table with keys that tell the module how to format. The table keys that can be used are:

• gap - a number with CSS units (px, em, en, etc) that define the size of the gap between numbers. If blank, the module will use 0.25em.
• prec - a number that determines the precision of the decimal part of the number. If the precision is less than the number of digits, extra digits will be removed without rounding; if it is more, zeroes will be added to the end to create the desired precision. If blank, the module will use -1, which means the precision will be the same as the number given; no digits added or removed.

Note that the return statement is a table. This means more styling or text can be added to the wrapper span tag, but it may also mean that tostring() may be required when used in other modules.

local gaps = require('Module:Gapnum').gaps

function example()
	local n = 123456.78900011
	-- Example for just simple formatting of a number
	-- n_gaps will use the default, .25em gaps and no change in precision
	-- The result will have its gaps created with inline css
	-- But the result would look like:
	-- 123 456.789 000 11
	local n_gaps = gaps(n)

	-- Different gap size
	-- These will format n into the same groups as above
	-- But the spaces between the groups will be larger and smaller, respectively
	local n_big_gaps = gaps(n, {gap='1em'})
	local n_small_gaps = gaps(n, {gap='1px'})

	-- Different precision
	-- n_prec_5 will use the number 123456.78900
	-- The result would look like:
	-- 123 456.789 00
	local n_prec_5 = gaps(n, {prec=5})
	-- n_prec_10 will use the number 123456.7890001100
	-- The result would look like:
	-- 123 456.789 000 1100
	local n_prec_10 = gaps(n, {prec=10})

	-- Both different gaps and precision can be used:
	local n_big_5 = gaps(n, {gap='1em', prec=5})
	local n_small_10 = gaps(n, {gap='1px', prec=10})
end

groups

The groups function can be used in other modules to separate a number into groups as gaps does, but instead of a formatted string, the function will return tables whose elements are the separated groups.

local groups = require('Module:Gapnum').groups

function example()
	-- This will return one table:
	-- {123,456}
	local n1 = groups(123456)

	-- This will return two tables, each assigned to a different variable:
	-- n2a will be:
	-- {1,234}
	-- n2b will be:
	-- {567,89}
	local n2a,n2b = groups(1234.56789)

	-- This will return two tables:
	-- An integer part is always returned, even if it is 0
	-- n3a will be:
	-- {0}
	-- n3b will be:
	-- {123,4567}
	local n3a,n3b = groups(0.1234567)

	-- Just like the other functions, a precision can be defined
	-- precision is simply the second parameter
	-- n4a will be:
	-- {123}
	-- n4b will be:
	-- {456,700,00}
	local n4a,n4b = groups(123.4567,8)
end

The above documentation is transcluded from Module:Gapnum/doc. (edit | history)
Editors can experiment in this module's sandbox (create | mirror) and testcases (create) pages.
Subpages of this module.

local p = {}

local getArgs

function p.main(frame)
	if not getArgs then
		getArgs = require('Module:Arguments').getArgs
	end
	local args = getArgs(frame, {wrappers = 'Template:Gapnum'})
	local gap =  args.gap or '0.25em'

	local ret_string = '<span style="white-space:nowrap">'

	local n = tonumber(args[1])
	
	if not n then
		if not args[1] then
			error('Nil value in parameter 1')
		else
			error('Unable to convert "' .. args[1] .. '" to a number')
		end
	end
	
	local nstr = tostring(n)
	local decimalloc = nstr:find('.', 1, true)
	local int_part, frac_part
	if decimalloc == nil then
		int_part = nstr
	else
		int_part = nstr:sub(1, decimalloc-1)
		frac_part = nstr:sub(decimalloc + 1)
	end
	
	local int_string = ''
	-- Loop to handle most of the groupings; from right to left, so that if a group has
	-- less than 3 members, it will be the first group
	while int_part:len() > 3 do
		int_string = '<span style="margin-left:'..gap..';">'..int_part:sub(-3)..'</span>'..int_string
		int_part = int_part:sub(1,-4)
	end
	
	-- handle any left over numbers
	int_string = int_part..int_string
	
	ret_string = ret_string..int_string
	
	local precision = tonumber(args.prec) or frac_part:len() or -1
	if precision > 0 and frac_part then
		local frac_string = '.'
		
		-- Reduce the length of the string if required precision is less than actual precision
		-- OR
		-- Increase it (by adding 0s) if the required precision is more than actual
		local offset = precision - frac_part:len()
		if offset < 0 then
			frac_part = frac_part:sub(1,precision)
		elseif offset > 0 then
			frac_part = frac_part .. string.rep('0', offset)
		end
		
		-- The first group after the decimal shouldn't have a gap between the decimal
		if frac_part:len() >= 3 then
			frac_string = frac_string..frac_part:sub(1,3)
			frac_part = frac_part:sub(4)
		else
			frac_string = frac_string..frac_part
			frac_part = ''
		end
		
	-- Loop to handle most of the groupings; from left to right, so that if a group has
	-- less than 3 members, it will be the last group
		while frac_part:len() >= 3 do
			frac_string = frac_string..'<span style="margin-left:'..gap..';">'..frac_part:sub(1,3)..'</span>'
			frac_part = frac_part:sub(4)
		end
	
		-- Handle any left over numbers
		if frac_part:len() > 0 then
			frac_string = frac_string..'<span style="margin-left:'..gap..';">'..frac_part..'</span>'
		end
		
		if frac_string:len() > 1 then
			ret_string = ret_string..frac_string
		end
	end
	
	-- Closing span tag
	ret_string = ret_string..'</span>'

	return ret_string
end

return p