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Modul:Chart

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Moduldokumentasjon

Mal:Template display Module Chart exports two functions: bar chart and pie chart

Note - Template:Graph:Chart is an alternative template, that may be more suitable for your use case.

Drawing Bar charts: "bar chart"

Parameters

parameter name what it does
delimiter string to delimit multiple values when given. default to colon ( : ). normally you do not want to touch this, it's provided for the off-chance you'll want to use colon as part of one of the parameters.
width number. if provided, must be at least 200. default: 500
height number. if provided, must be at least 200. default: 350
group n (where "n" is a number. use "group 1", "group 2" etc. for as many groups as there are in the graph) the values to be charted. see below.
tooltip n tooltip to be associated with specific bar. If no tooltip for a specific bar is defined, and this bar has a link, then this link will be used as tooltip. Otherwise, the tooltip will be combined from the group name and the value, optionally with "units prefix" and "units suffix".
links n links to articles to be associated with specific bar
stack whether to stack the different groups on top of each other. do not specify to show bars side by side. Any non-empty value means "yes". To say "no", simply do not supply this parameter at all, or leave the value blank.
tooltip value accumulation useful only with stack: when set to true, tooltip will show accumulated value of all blocks up to current one
colors the colors used to denote the various groups. should have exactly as many values as # of groups. can be given as standard html-recognized color names, or using #xxx or #xxxxxx notation.
x legends The legends for the X values. Wikicode, such as internal links or templates can be used.
hide group legends if set to true, group legends will not be shown below chart. Any non-empty value means "yes". To say "no", simply do not supply this parameter at all, or leave the value blank.
scale per group set to use separate Y- scale for each group. leave empty to use one scale for all groups. incompatible with "stack". Note that even if some of the scales are exactly the same, they will be drawn separately when this setting is on. Any non-empty value means "yes". To say "no", simply do not supply this parameter at all, or leave the value blank.
units prefix used in tooltip. e.g., $, so values will show as "$500" instead of "500" in the tooltip
units suffix ditto for units suffix. use, e.g. "Kg" so values will show as 88Kg instead of 88 in tooltip. underscore ("_") are replaced by spaces, to allow a space between the value and the suffix.
group names names of different groups
y tick marks number of tick marks on the y axis. if the value is negative or omitted, the module will attempt to automatically calculate a sensible number of tick marks.

Display in the mobile view

Bar charts behave unpredictably, causing problems with the axes and legend. Use Template:Graph:Chart instead. Mal:Dubious span

Examples

Basic

{{ #invoke:Chart | bar chart
| group 1 = 40 : 50 : 60 : 20
| group 2 = 20 : 60 : 12 : 44
| group 3 = 55 : 14 : 33 : 5
| links 1 = Apple : McCintosh : Golden delicious
| links 2 = Banana : Apricot : Peach
| links 3 = Orange : Pear : Bear
| tooltip 2 = tooltip 1 : tooltip 2 : tooltip 3 : tooltip 4
| colors = green : yellow : orange
| group names = Apple : Banana : Orange
| x legends = Before : During : After : Post mortem
}}


Skriptfeil: Funksjonen «bar chart» eksisterer ikke.


Stacked

Here is the same graph, with more modest height and width, using "stack", and adding "units suffix" for good measure:

{{ #invoke:Chart | bar chart
| height = 250
| width = 300
| stack = 1
| group 1 = 40 : 50 : 60 : 20
| group 2 = 20 : 60 : 12 : 44
| group 3 = 55 : 14 : 33 : 5
| colors = green : yellow : orange
| group names = Apple : Banana : Orange
| units suffix = Kg
| x legends = Before : During : After : Post mortem
}}

Skriptfeil: Funksjonen «bar chart» eksisterer ikke.


Scale per group

This option has been disabled. It was rarely used and broke in the last code update. Here is an example with large number of groups - mainly to test how it looks with large number of legends:

{{ #invoke:Chart | bar chart
| width = 800
| height = 550
| group 1 = 1:2:3:4:5:4:3:2:1
| group 2 = 1:2:3:4:5:4:3:2:1
| group 3 = 1:2:3:4:5:4:3:2:1
| group 4 = 1:2:3:4:5:4:3:2:1
| group 5 = 1:2:3:4:5:4:3:2:1
| group 6 = 1:2:3:4:5:4:3:2:1
| group 7 = 1:2:3:4:5:4:3:2:1
| group 8 = 1:2:3:4:5:4:3:2:1
| group 9 = 1:2:3:4:5:4:3:2:1
| group 10 = 1:2:3:4:5:4:3:2:1
| group 11 = 1:2:3:4:5:4:3:2:1
| group 12 = 1:2:3:4:5:4:3:2:1
| group 13 = 1:2:3:4:5:4:3:2:1
| group 14 = 1:2:3:4:5:4:3:2:1
| group 15 = 1:2:3:4:5:4:3:2:1
| group 16 = 1:2:3:4:5:4:3:2:1
| group 17 = 1:2:3:4:5:4:3:2:1
| group 18 = 1:2:3:4:5:4:3:2:1
| group 19 = 1:2:3:4:5:4:3:2:1
| group 20 = 1:2:3:4:5:4:3:2:1
| group 21 = 1:2:3:4:5:4:3:2:1
| colors = Silver:Gray:Black:Red:Maroon:Yellow:Olive:Lime:Green:Aqua:Teal:Blue:Navy:Fuchsia:Purple:ForestGreen:Tomato:LightSeaGreen:RosyBrown:DarkOliveGreen:MediumVioletRed
| group names = Alabama:Alaska:Arizona:Arkansas:California:Colorado:Connecticut:Delaware:Florida:Georgia:Hawaii:Idaho:Illinois:Indiana:Iowa:Kansas:Kentucky:Louisiana:Maine:Maryland:Massachusetts
| x legends = 1920 : 1930 : 1940: 1950 : 1960 : 1970 : 1990 : 2000 : 2010
| units prefix = $
| units suffix = _billion
| stack = 1
}}

Skriptfeil: Funksjonen «bar chart» eksisterer ikke.


If there are many values, x legends can be diluted by using delimiters with nothing in between:

{{ #invoke:Chart | bar chart
| group 1 = 1:2:3:4:5:6:7:8:9:10:11:12:13:14:15:16:17:18:19:20:21:22:23:24:25:26:27:28:29:30
:31:32:33:34:35:36:37:38:39:40:41:42:43:44:45:46:47:48:49:50:51:52:53:54:55:56:57:58:59
| units suffix = _Things
| group names = Some
| x legends = ::::1940::::::::::1950::::::::::1960::::::::::1970::::::::::1980::::::::::1990::::
}}

Skriptfeil: Funksjonen «bar chart» eksisterer ikke.

Drawing Pie charts: "pie chart"

Parameters

parameter name what it does
delimiter string to delimit multiple values when given. default to colon ( : ). normally you do not want to touch this, it's provided for the off-chance you'll want to use colon as part of one of the parameters.
radius number. The radius of the pie in pixels
slices Tuples, in parenthesis. Use delimiter inside the tuple:
( Value1 : Name1 : Color1 : Link1  ) ( Value2 : Name2 : Color2 : Link2 ) ...

The values are numbers. The numbers can be integers or decimal fractions, or using the scientific notation: 7.24e6, 7,240,000, or 7240000.00 are all acceptable for 7 Million and 240 thousands.

Names are strings. Colors are optional. you can use any Web colors, such as "red" or "#FF0000". Up to 26 default colors are defined, but if your pie has more than 26 slices, you must define the colors of slice #27 and up. Links can be external or internal links, including linking to internal anchors and paragraphs in the same article, like so: [[Article|Tooltip]] for internal link, [[#Paragraph name|Tooltip]] for linking to an anchor in same article, or [http://example.org Tooltip] for external link.

slice n alternative syntax to "slices". n is the slice number, beginning with 1. make sure not to skip: if you define "slice 1", "slice 2", "slice 4", "slice 5"..., skipping slice 3, only the first two slices will be shown. this syntax is incompatible with "slices", i.e., they should not be used in conjunction in the same invocation. Using both "slices" and "slice n" in the same invocation will cause unpredictable results. The value is like a single "tuple" as explained above, but without the parenthesis:
 | slice 1 = Value1 : Name1 : Color1 : Link1
 | slice 2 = Value2 : Name2 : Color2 : Link2
 | ...

This syntax allows you to use parenthesis in names, links, and colors.

percent if used, the percentage of each slice will be calculated and added to the legend: so if you have two slices, like so: ( 1 : Younglings ) ( 3 : elders ), and use define "percent", the legends will become "Younglings: 1 (25%)" and "Elders: 3 (75%)", instead of simply "Younglings: 1" and "Elders: 3". Any non-empty value means "yes". To say "no", simply do not supply this parameter at all, or leave the value blank.
units prefix used in the legend. e.g., defining "units prefix=$", values will show as "$500" instead of "500" in the legends
units suffix ditto for units suffix. use, e.g. "Kg" so values will show as 88Kg instead of 88 in legend. underscore ("_") are replaced by spaces, to allow a space between the value and the suffix.
hide group legends Setting to true prevents displaying of the group legends under the chart. Any non-empty value means "yes". To say "no", simply do not supply this parameter at all, or leave the value blank.

Examples

Skriptfeil: Funksjonen «pie chart» eksisterer ikke.

Skriptfeil: Funksjonen «pie chart» eksisterer ikke.

--[[
next 100 lines or so are copied from mw.text package, which is not yet available.
once this library is added to wmf distributions, all functions and variables that look lke "mw.text.XXX
should be removed.
]]
u = require( "libraryUtil" )
mw = mw or {}
mw.text = mw.text or {}
local htmlencode_map = {
    ['>'] = '>',
    ['<'] = '&lt;',
    ['&'] = '&amp;',
    ['"'] = '&quot;',
    ["'"] = '&#039;',
    ['\194\160'] = '&#nbsp;',
}
local htmldecode_map = {}
for k, v in pairs( htmlencode_map ) do
    htmldecode_map[v] = k
end
local decode_named_entities = nil

function mw.text.encode( s, charset )
    charset = charset or '<>&"\'\194\160'
    s = mw.ustring.gsub( s, '[' .. charset .. ']', function ( m )
        if not htmlencode_map[m] then
            local e = string.format( '&#%d;', mw.ustring.codepoint( m ) )
            htmlencode_map[m] = e
            htmldecode_map[e] = m
        end
        return htmlencode_map[m]
    end )
    return s
end
function mw.text.split( text, pattern, plain )
    local ret = {}
    for m in gsplit( text, pattern, plain ) do
        ret[#ret+1] = m
    end
    return ret
end

function mw.text.gsplit( text, pattern, plain )
    local s, l = 1, mw.ustring.len( text )
    return function ()
        if s then
            local e, n = mw.ustring.find( text, pattern, s, plain )
            local ret
            if not e then
                ret = mw.ustring.sub( text, s )
                s = nil
            elseif n < e then
                -- Empty separator!
                ret = mw.ustring.sub( text, s, e )
                if e < l then
                    s = e + 1
                else
                    s = nil
                end
            else
                ret = e > s and mw.ustring.sub( text, s, e - 1 ) or ''
                s = n + 1
            end
            return ret
        end
    end, nil, nil
end

function mw.text.tag( name, attrs, content )
    local named = false
    if type( name ) == 'table' then
        named = true
        name, attrs, content = name.name, name.attrs, name.content
        u.checkTypeForNamedArg( 'tag', 'name', name, 'string' )
        u.checkTypeForNamedArg( 'tag', 'attrs', attrs, 'table', true )
    else
        u.checkType( 'tag', 1, name, 'string' )
        u.checkType( 'tag', 2, attrs, 'table', true )
    end

    local ret = { '<' .. name }
    for k, v in pairs( attrs or {} ) do
        if type( k ) ~= 'string' then
            error( "bad named argument attrs to 'tag' (keys must be strings, found " .. type( k ) .. ")",
2 )
        end
        if string.match( k, '[\t\r\n\f /<>"\'=]' ) then
            error( "bad named argument attrs to 'tag' (invalid key '" .. k .. "')", 2 )
        end
        local tp = type( v )
        if tp == 'boolean' then
            if v then
                ret[#ret+1] = ' ' .. k
            end
        elseif tp == 'string' or tp == 'number' then
            ret[#ret+1] = string.format( ' %s="%s"', k, mw.text.encode( tostring( v ) ) )
        else
            error( "bad named argument attrs to 'tag' (value for key '" .. k .. "' may not be " .. tp .. ")", 2 )
        end
    end

    local tp = type( content )
    if content == nil then
        ret[#ret+1] = '>'
    elseif content == false then
        ret[#ret+1] = ' />'
    elseif tp == 'string' or tp == 'number' then
        ret[#ret+1] = '>'
        ret[#ret+1] = content
        ret[#ret+1] = '</' .. name .. '>'
    else
        if named then
            u.checkTypeForNamedArg( 'tag', 'content', content, 'string, number, nil, or false' )
        else
            u.checkType( 'tag', 3, content, 'string, number, nil, or false' )
        end
    end

    return table.concat( ret )
end

function mw.text.trim( s )
    return mw.ustring.match(s, "^%s*(.-)%s*$")
end
-- everything up to this point should be removed once mw.text becomes available.
function barChart( frame )
    local res = {}
    local args = frame.args -- can be changed to frame:getParent().args
    local values, xlegends, colors, tooltips, yscales = {}, {}, {}, {} ,{}, {}, {}
    local groupNames, unitsSuffix, unitsPrefix = {}, {}, {}
    local width, height, stack, delimiter = 500, 350, false, ':'
    local chartWidth, chartHeight, defcolor, scalePerGroup

    local keywords = {
        width = 'width',
        height = 'height',
        stack = 'stack',
        colors = 'colors',
        group = 'group',
        xlegend = 'x legend',
        yscale = 'y scale',
        tooltip = 'tooltip',
        defcolor = 'default color',
        scalePerGroup = 'scale per group',
        unitsPrefix = 'units prefix',
        unitsSuffix = 'units suffix',
        groupNames = 'group names',
    } -- here is where you want to translate

    local numGroups, numValues
    local scaleWidth

    function validate()
        function asGroups( name, tab, toDuplicate, emptyOK )
            if #tab == 0 and not emptyOK then
                error( "must supply values for " .. keywords[name] )
            end
            if #tab == 1 and toDuplicate then
                for i = 2, numGroups do tab[i] = tab[1] end
            end
            if #tab > 0 and #tab ~= numGroups then
                error ( keywords[name] .. ' should contain the same number of items as the number of groups (' .. numGroups .. ')')
            end
        end

        -- do all sorts of validation here, so we can assume all params are good from now on.
        -- among other things, replace numerical values with mw.language:parseFormattedNumber() result


        chartHeight = height - 80
        numGroups = #values
        numValues = #values[1]
        defcolor = defcolor or 'blue'
        scaleWidth = scalePerGroup and 40 * numGroups or 60
        chartWidth = width -scaleWidth
        asGroups( 'unitsPrefix', unitsPrefix, true, true )
        asGroups( 'unitsSuffix', unitsSuffix, true, true )
        asGroups( 'colors', colors, true, true )
        asGroups( 'groupNames', groupNames, false, false )
        if stack and scalePerGroup then
            error( string.format( 'Illegal settings: %s and %s are incompatible.', keyword.stack, keyword.scalePerGroup ) )
        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.scalePerGroup then scalePerGroup = true
            elseif k == keywords.defcolor then defcolor = v
            else
                for keyword, tab in pairs( {
                    group = values,
                    xlegend = xlegends,
                    colors = colors,
                    tooltip = tooltips,
                    unitsPrefix = unitPrefix,
                    unitsSuffix = unitsSuffix,
                    groupNames = groupNames,
                    } ) 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 ithem, otherwise calculate. for "stack" there's only one limet.
        if #yscales > 0 then return end
        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 = roundup( 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 ) end
        if not scalePerGroup then for i = 1, #values do yscales[i] = math.max( unpack( yscales ) ) end end
    end

    function tooltip( gi, i, val )
        function nulOrWhitespace( s )
            return not s or mw.text.trim( s ) == ''
        end

        if tooltips and tooltips[gi] and not nulOrWhitespace( tooltips[gi][i] ) then return tooltips[gi][i] 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 groupName .. prefix .. val .. suffix
    end

    function calcHeights( gi, i, val )
        local barHeight = math.floor( val / yscales[gi] * chartHeight )
        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 )
        setWidth = 0.85 * setWidth
        if stack then
            local barWidth = math.min( 38, math.floor( 0.8 * setWidth ) )
            return setOffset + (setWidth - barWidth) / 2, barWidth
        end
        local barWidth = math.floor( 0.75 * setWidth / numGroups )
        local left = setOffset + math.floor( ( gi - 1 ) / numGroups * setWidth )
        return left, barWidth
    end

    function drawbar( gi, i, val )
        local color, tooltip = colors[gi] or defcolor or 'blue', tooltip( gi, i, val )
        local left, barWidth = calcx( gi, i )
        local barHeight, top = calcHeights( gi, i, val )
        local style = string.format("position:absolute;left:%spx;top:%spx;height:%spx;min-width:%spx;max-width:%spx;background-color:%s;box-shadow:4px -3px 3px 1px grey;",
                        left, top, barHeight, barWidth, barWidth, color)
        table.insert( res, mw.text.tag( 'div', { style = style, title = tooltip, }, "" ) )
    end


    function drawYScale()
        function drawSingle( gi, color, width, single )
            local yscale = yscales[gi]
            local _, top, ordermag = roundup( yscale * 0.999 )
            local numnotches = top <= 1.5 and top * 4
                    or top < 4  and top * 2
                    or top
            local valStyleStr =
                single and 'position:absolute;height=20px;text-align:right;vertical-align:middle;width:%spx;top:%spx;padding:0 2px'
                or 'position:absolute;height=20px;text-align:right;vertical-align:middle;width:%spx;top:%spx;left:3px;background-color:%s;color:white;font-weight:bold;text-shadow:-1px -1px 0 #000,1px -1px 0 #000,-1px 1px 0 #000,1px 1px 0 #000;padding:0 2px'
            local notchStyleStr = 'position:absolute;height=1px;min-width:5px;top:%spx;left:%spx;border:1px 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 ) }, val )
                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 -- not ready yet/
            local colWidth = 40
            local colStyle = "position:absolute;height:%spx;min-width:%spx;left:%spx;border-right:1px solid %s;color:%s"
            for gi = 1, numGroups do
                local left = ( gi - 1 ) * 40
                local color = colors[gi] or defcolor
                table.insert( res, mw.text.tag( 'div', { style = string.format( colStyle, chartHeight, colWidth, left, color, color ) } ) )
                drawSingle( gi, color, colWidth )
                table.insert( res, '</div>' )
            end
        else
            drawSingle( 1, 'black', scaleWidth, true )
        end
    end

    function drawXlegends()
        local setOffset, setWidth
        local legendDivStyleFormat = "position:absolute;left:%spx;top:10px;min-width:%spx;max-width:%spx;text-align:center;veritical-align:top;"
        local tickDivstyleFormat = "position:absolute;left:%spx;height:10px;width:1px;border-left:1px solid black;"
        for i = 1, numValues do
            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 - 10 ) }, '' ) )
        end
    end

    function printGroupList()
        if #groupNames > 0 then
            local list = {}
            for gi = 1, #groupNames do
                local square = mw.text.tag( 'span', { style = string.format( 'background-color:%s;padding:0 0.5em;margin:0 0.5em;', colors[gi] or defcolor ) }, ' ' )
                table.insert( list, '*' .. square .. ' ' .. groupNames[gi] )
            end
            table.insert( res, table.concat( list, '\n' ) )
        end
    end

    function drawChart()
        table.insert( res, mw.text.tag( 'div', { style = string.format( 'max-width:%spx;', width ) } ) )
        table.insert( res, mw.text.tag( 'div', { style = string.format("min-height:%spx;min-width:%spx;max-width:%spx;", height, width, width ) } ) )

        table.insert( res, mw.text.tag( 'div', { style = string.format("float:right;position:relative;min-height:%spx;min-width:%spx;max-width:%spx;border-left:1px black solid;border-bottom:1px black solid;", chartHeight, chartWidth, chartWidth ) } ) )

         for gi, group in pairs( values ) do
             for i, val in ipairs( group ) do
                drawbar( gi, i, val )
            end
        end

        table.insert( res, '</div>' )
        table.insert( res, mw.text.tag( 'div', { style = string.format("position:absolute;height:%s;min-width:%s;max-width:%spx;", chartHeight, scaleWidth, scaleWidth, scaleWidth ) } ) )
        drawYScale()
        table.insert( res, '</div>' )
        table.insert( res, mw.text.tag( 'div', { style = string.format("float:right;position:relative;width:%spx;", chartWidth ) } ) )
        drawXlegends()
        table.insert( res, '</div>' )
        table.insert( res, '</div>' )
        printGroupList()
        table.insert( res, '</div>' )
    end

    extractParams()
    validate()
    calcHeightLimits()
    drawChart()
    return table.concat( res, "\n" )
end

return { ['bar-chart'] = barChart }