end
if #xlegends ~= numValues then error( 'Illegal number of ' .. keywords.xlegend .. '. Should be exactly ' .. numValues ) end
end  
function extractParams
function testone( keyword, key, val, tab )
i = keyword == key and 0 or key:match( keyword .. "%s+(%d+)" )
if not i then return end
i = tonumber( i ) or error("Expect numerical index for key " .. keyword .. " instead of '" .. key .. "'")
if i > 0 then tab[i] = {} end
for s in mw.text.gsplit( val, '%s*' .. delimiter .. '%s*' ) do
table.insert( i == 0 and tab or tab[i], s )
end
return true
end  
for k, v in pairs( args ) do
if k == keywords.width then
width = tonumber( v )
if not width or width < 200 then
error( 'Illegal width value (must be a number, and at least 200): ' .. v )
end
elseif k == keywords.height then
height = tonumber( v )
if not height or height < 200 then
error( 'Illegal height value (must be a number, and at least 200): ' .. v )
end
elseif k == keywords.stack then stack = true
elseif k == keywords.yticks then yticks = tonumber(v) or -1
elseif k == keywords.scalePerGroup then scalePerGroup = true
elseif k == keywords.defcolor then defcolor = v
elseif k == keywords.accumulateTooltip then accumulateTooltip = not nulOrWhitespace( v )
elseif k == keywords.hideGroupLegends then hideGroupLegends = not nulOrWhitespace( v )
else
for keyword, tab in pairs( {
group = values,
xlegend = xlegends,
colors = colors,
tooltip = tooltips,
unitsPrefix = unitsPrefix,
unitsSuffix = unitsSuffix,
groupNames = groupNames,
links = links,
} ) do
if testone( keywords[keyword], k, v, tab )
then break
end
end
end
end
end  
function roundup( x ) -- returns the next round number: eg., for 30 to 39.999 will return 40, for 3000 to 3999.99 wil return 4000. for 10 - 14.999 will return 15.
local ordermag = 10 ^ math.floor( math.log10( x ) )
local normalized = x / ordermag
local top = normalized >= 1.5 and ( math.floor( normalized + 1 ) ) or 1.5
return ordermag * top, top, ordermag
end  
function calcHeightLimits -- if limits were passed by user, use them, otherwise calculate. for "stack" there's only one limet.
if stack then
local sums = {}
for _, group in pairs( values ) do
for i, val in ipairs( group ) do sums[i] = ( sums[i] or 0 ) + val end
end
local sum = math.max( unpack( sums ) )
for i = 1, #values do yscales[i] = sum end
else
for i, group in ipairs( values ) do yscales[i] = math.max( unpack( group ) ) end
end
for i, scale in ipairs( yscales ) do yscales[i] = roundup( scale * 0.9999 ) end
if not scalePerGroup then for i = 1, #values do yscales[i] = math.max( unpack( yscales ) ) end end
end  
function tooltip( gi, i, val )
if tooltips and tooltips[gi] and not nulOrWhitespace( tooltips[gi][i] ) then return tooltips[gi][i], true end
local groupName = not nulOrWhitespace( groupNames[gi] ) and groupNames[gi] .. ': ' or ''
local prefix = unitsPrefix[gi] or unitsPrefix[1] or ''
local suffix = unitsSuffix[gi] or unitsSuffix[1] or ''
return mw.ustring.gsub(groupName .. prefix .. mw.getContentLanguage:formatNum( tonumber( val ) or 0 ) .. suffix, '_', ' '), false
end  
function calcHeights( gi, i, val )
local barHeight = math.floor( val / yscales[gi] * chartHeight + 0.5 ) -- add half to make it "round" instead of "trunc"
local top, base = chartHeight - barHeight, 0
if stack then
local rawbase = 0
for j = 1, gi - 1 do rawbase = rawbase + values[j][i] end -- sum the "i" value of all the groups below our group, gi.
base = math.floor( chartHeight * rawbase / yscales[gi] ) -- normally, and especially if it's "stack", all the yscales must be equal.
end
return barHeight, top - base
end  
function groupBounds( i )
local setWidth = math.floor( chartWidth / numValues )
local setOffset = ( i - 1 ) * setWidth
return setOffset, setWidth
end  
function calcx( gi, i )
local setOffset, setWidth = groupBounds( i )
if stack or numGroups == 1 then
local barWidth = math.min( 38, math.floor( 0.8 * setWidth ) )
return setOffset + (setWidth - barWidth) / 2, barWidth
end
setWidth = 0.85 * setWidth
local barWidth = math.floor( 0.75 * setWidth / numGroups )
local = setOffset + math.floor( ( gi - 1 ) / numGroups * setWidth )
return , barWidth
end  
function drawbar( gi, i, val, ttval )
if val == '0' then return end -- do not show single line (borders....) if value is 0, or rather, '0'. see talkpage  
local color, tooltip, custom = colors[gi] or defcolor or 'blue', tooltip( gi, i, ttval or val )
local , barWidth = calcx( gi, i )
local barHeight, top = calcHeights( gi, i, val )  
-- borders so it shows up when printing
local style = string.format("position:absolute;:%spx;top:%spx;height:%spx;min-width:%spx;max-width:%spx;background-color:%s;-webkit-print-color-adjust:exact;: solid %s;-bottom:;overflow:hidden;",
, top, barHeight-1, barWidth-2, barWidth-2, color, color)
local link = links[gi] and links[gi][i] or ''
local img = not nulOrWhitespace( link ) and mw.ustring.format( *, link, custom and tooltip or * ) or ''
table.insert( res, mw.text.tag( 'div', { style = style, title = tooltip, }, img ) )
end  
function drawYScale
function drawSingle( gi, color, width, yticks, single )
local yscale = yscales[gi]
local _, top, ordermag = roundup( yscale * 0.999 )
local numnotches = yticks >= 0 and yticks or
(top <= 1.5 and top * 4
or top < 4 and top * 2
or top)
local valStyleStr =
single and 'position:absolute;height=;text-align:;vertical-align:middle;width:%spx;top:%spx;padding:0 '
or 'position:absolute;height=;text-align:;vertical-align:middle;width:%spx;top:%spx;:;background-color:%s;color:white;font-weight:bold;text-shadow:- - 0 #000, - 0 #000,- 0 #000, 0 #000;padding:0 '
local notchStyleStr = 'position:absolute;height=;min-width:;top:%spx;:%spx;: solid %s;'
for i = 1, numnotches do
local val = i / numnotches * yscale
local y = chartHeight - calcHeights( gi, 1, val )
local div = mw.text.tag( 'div', { style = string.format( valStyleStr, width - 10, y - 10, color ) }, mw.getContentLanguage:formatNum( tonumber( val ) or 0 ) )
table.insert( res, div )
div = mw.text.tag( 'div', { style = string.format( notchStyleStr, y, width - 4, color ) }, '' )
table.insert( res, div )
end
end  
if scalePerGroup then
local colWidth = 80
local col
for gi = 1, numGroups do
local = ( gi - 1 ) * colWidth
local color = colors[gi] or defcolor
table.insert( res, mw.text.tag( 'div', { style = string.format( colStyle, chartHeight, colWidth, , color, color ) } ) )
drawSingle( gi, color, colWidth, yticks )
table.insert( res, '</div>' )
end
else
drawSingle( 1, 'black', scaleWidth, yticks, true )
end
end  
function drawXlegends
local setOffset, setWidth
local legendDivStyleFormat = "position:absolute;:%spx;top:;min-width:%spx;max-width:%spx;text-align:;vertical-align:top;"
local tickDivstyleFormat = "position:absolute;:%spx;height:;width:;-: solid black;"
for i = 1, numValues do
if not nulOrWhitespace( xlegends[i] ) then
setOffset, setWidth = groupBounds( i )
-- setWidth = 0.85 * setWidth
table.insert( res, mw.text.tag( 'div', { style = string.format( legendDivStyleFormat, setOffset + 5, setWidth - 10, setWidth - 10 ) }, xlegends[i] or '' ) )
table.insert( res, mw.text.tag( 'div', { style = string.format( tickDivstyleFormat, setOffset + setWidth / 2 ) }, '' ) )
end
end
end  
function drawChart
table.insert( res, mw.text.tag( 'div', {, style = string.format( 'margin-top:1em;max-width:%spx;', width ) } ) )
table.insert( res, mw.text.tag( 'div', { style = string.format("position:relative;min-height:%spx;min-width:%spx;max-width:%spx;", height, width, width ) } ) )  
table.insert( res, mw.text.tag( 'div', { style = string.format("float:;position:relative;min-height:%spx;min-width:%spx;max-width:%spx;-: black solid;-bottom: black solid;", chartHeight, chartWidth, chartWidth ) } ) )
local acum = stack and accumulateTooltip and {}
for gi, group in pairs( values ) do
for i, val in ipairs( group ) do
if acum then acum[i] = ( acum[i] or 0 ) + val end
drawbar( gi, i, val, acum and acum[i] )
end
end
table.insert( res, '</div>' )