SVG Scatter charts API reference

Summary
Documentation about the SVG Scatter chart including information on all the options and methods that are available to you.

 

Example

The code below produces a chart like this:

<script>
    var data = [
        {x:16,y:42},{x:15,y:43},{x:58,y:12},{x:84,y:23},{x:65,y:46},{x:221,y:18},{x:263,y:43},{x:121,y:50},
        {x:215,y:12},{x:222,y:32},{x:344,y:12},{x:123,y:32},{x:2,y:50},{x:355,y:23},{x:125,y:15},{x:85,y:41}
    ];
    
    new RGraph.SVG.Scatter({
        id: 'chart-container',
        data: data,
        options: {
            xaxisMax: 365,
            xaxisLabels: ['Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec'],
            tickmarksStyle: 'plus',
            colors: ['red']
        }
    }).draw();
</script>

 

How to specify the Scatter chart data

The Scatter chart is a touch different than other charts because whereas they (usually) use arrays of information to specify values the Scatter chart uses an array of objects. This should come quite naturally though as each Scatter chart point can have several different attributes (eg X value, Y value, tooltip etc). At its most basic it looks like this:

    var data = [
        {x:5,y:7}, {x:7,y:9}, {x:1,y:3}
    ];

That would define three points, each with X and Y values. There are other things that you can add to each object (or just one/two etc) and they are:

Another example where each point has all of the options specified is:

    var data = [
        {x:5,y:7,type: 'triangle',color: 'green', size: 10,opacity: 0.75,tooltip: 'The first tickmark'},
        {x:7,y:9,type: 'square',color: 'red', size: 15,opacity: 0.5,tooltip: 'The second tickmark'},
        {x:1,y:3,type: 'cross',color: 'cyan', size: 15,opacity: 0.25,tooltip: 'The third tickmark'}
    ];

 

Using dates and times instead of numeric X values

Instead of numeric X values, you can instead give a datetime string that RGraph will parse (using the RGraph.SVG.parseDate() function) and use as the value instead. The xaxisMin and xaxisMax values can also be specified like this too. The format of the datetime string can be varied (as you can see from the example below). Here's an example of a datetime chart.

<script>
    data = [
        {x:'23:59 15-01-2012', y:5},
        {x:'2012 15th February', y:6},
        {x:'Mar 15 2012', y:6},
        {x:'2012/04/15', y:6},
        {x:'2012-05.15', y:5},
        {x:'2012 June 15', y:4},
        {x:'July 2012 15th', y:5},
        {x:'aug 15th 2012', y:6},
        {x:'15th september 2012', y:7},
        {x:'15 Oct 2012', y:6},
        {x:'2012.11.15', y:4},
        {x:'2012.12-15 00:00:00', y:5}
    ];
    
    new RGraph.SVG.Scatter({
        id: 'chart-container',
        data: data,
        options: {
            backgroundGridVlines: false,
            backgroundGridBorder: false,
            yaxis: false,
            colors: ['red'],
            title: 'A Scatter chart using datetime values',
            xaxisMin: '2012/01/06 12:14:12',
            xaxisMax: '31st dec 2012'
        }
    }).draw();
</script>

 

Using image based tickmarks

If the list of tickmarks does not suit your needs you can use an image as your tickmark instead. You can specify one by doing this:

<script>
    new RGraph.SVG.Scatter({
        id: 'image-based-tickmarks',
        data: [
            {x: 50, y: 26, type:'image:/images/logo.png'},
            {x: 100, y: 26, type:'image:/images/coins.png'},
            {x: 150, y: 26, type:'image:/images/atom.png'},
            {x: 200, y: 26, type:'image:/images/alert.png'},
            {x: 250, y: 26, type:'image:/images/alex.png'}
        ],
        options: {
            title: 'A Scatter chart using image based tickmarks',
            xaxisMin: 0,
            xaxisMax: 365,
            xaxisLabels: ['Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec']
        }
    }).draw();
</script>

 

Adding a line connecting the tickmarks

By using the line option you can have a line connecting the points therefore creating a line chart - but with this line chart (instead of the regular line chart ) the points are not neccarsarily a fixed width apart - the X value is totally down to you along with the Y value. The datetime chart above is also showing an example of using the line option.

 

Properties

You can use these properties to control how the chart apears. You can set them by including them in the options section of the configuration as above.

Layout style:     
  

Background

PropertyDescriptionDefault
backgroundColorThe color of the background.null
backgroundImageA URL of an image to render to the backgroundnull
backgroundImageAspectThe aspect ration setting of the SVG image tag, eg it could be XMinYMin meetnone
backgroundImageOpacityThe alpha/opacity value of the background image.0.5
backgroundImageStretchWhether the background image is stretched across the whole chart (except the gutters).true
backgroundImageXIf you're not using the stretch option you can specify the X coordinate of the image.null
backgroundImageXIf you're not using the stretch option you can specify the Y coordinate of the image.null
backgroundImageWIf you're not using the stretch option you can specify the width of the image.null
backgroundImageHIf you're not using the stretch option you can specify the height of the image.null
backgroundGridWhether to show the background grid or not.true
backgroundGridColorThe color of the background grid.#ddd
backgroundGridLinewidthThe linewidth that the background grid lines are. Decimals (eg 0.5) are permitted.1
backgroundGridBorderDetermines whether a border line is drawn around the grid.true
backgroundGridHlinesDetermines whether to draw the horizontal grid lines.true
backgroundGridHlinesCountDetermines how many horizontal grid lines you have. The default is linked to how many scale labels that you have.null
backgroundGridVlinesDetermines whether to draw the vertical grid lines.true
backgroundGridVlinesCountDetermines how many vertical grid lines you have. The default is to be linked to how many scale labels that you have.null

Margins

PropertyDescriptionDefault
gutterLeftThe left gutter of the chart, (the gutter is where the labels and title are)).35
gutterRightThe right gutter of the chart, (the gutter is where the labels and title are).35
gutterTopThe top gutter of the chart, (the gutter is where the labels and title are).35
gutterBottomThe bottom gutter of the chart, (the gutter is where the labels and title are).35

Colors

PropertyDescriptionDefault
colorsAn array of the colors of the bars.null

Tickmarks

PropertyDescriptionDefault
tickmarksStyleThe style of the tickmarks. This can be a string, or it can also be an array of different types which are used on a per-dataset basis. You can also specify the type: attribute in the data set (see above). Possible types are:
  • cross
  • image:xxx
  • triangle
  • plus
  • square (or rect)
  • circle (or dot)
cross
tickmarksSizeThe size of the tickmarks. It can be a number or an array of numbers, one for each dataset. This can be overridden on a per-point basis by using the size property in each points configuration data.7

X axis

PropertyDescriptionDefault
xaxisWhether the X axis is shown or not.true
xaxisLinewidthThe linewidth thats used to draw the X axis.1
xaxisTickmarksWhether the X axis has tickmarks or not.true
xaxisTickmarksLengthThe size of the X axis tickmarks5
xaxisLabelsOffsetxThe X pixel offset thats added to the X axis labels.0
xaxisLabelsOffsetyThe Y pixel offset thats added to the X axis labels.0
xaxisColorThe color of the X axis.black
xaxisTextColorThe color of the X axis text (this overrides the textColor option)null
xaxisTextBoldWhether the X axis text is bold or not (this overrides the textColor option)null
xaxisTextItalicWhether the X axis text is italic or not (this overrides the textItalic option)null
xaxisTextFontThe font of the X axis text (this overrides the textFont option)null
xaxisTextSizeThe size of the X axis text (this overrides the textSize option)null

Y axis

PropertyDescriptionDefault
yaxisWhether the Y axis is shown or not.true
yaxisColorThe color of the Y axis.black
yaxisLinewidthThe linewidth thats used to draw the Y axis.1
yaxisTickmarksWhether the Y axis has tickmarks or not.true
yaxisTickmarksLengthThe size of the Y axis tickmarks5
yaxisScaleWhether the the Y axis scale is shown.true
yaxisLabelsIf the yaxisScale option is false then this can be used to give an array of labels that are shown on the Y axis instead.null
yaxisLabelsOffsetxThe X pixel offset thats added to the Y axis labels.0
yaxisLabelsOffsetyThe Y pixel offset thats added to the Y axis labels.0
yaxisLabelsCountThe number of Y labels.5
yaxisUnitsPreUnits that are prepended to the scale numbers. (An empty string
yaxisUnitsPostUnits that are appended to the scale numbers.(An empty string
yaxisDecimalsThe number of decimals that the scale will show.0
yaxisPointThe character(s) used as the decimal point..
yaxisThousandThe character(s) used as the thousand seperator.,
yaxisRoundIf set to true the max scale value will be rounded up.false
yaxisMaxThe maximum scale value (you will need to set yaxisStrict to true if you want the maximum value to be exactly this value).null
yaxisMinThe minimum Y value. As well as a numeric value you can also set this to mirror so that the X axis is put in the center.0
yaxisFormatterThis option should be a function. This function handles the entirety of the number formatting for the yaxis. Units are not added, decimals are not added - its all up to you. The function is passed two arguments - the chart object and the number. It should look like this:
yaxisFormatter: function (obj, num)
{
}
null
yaxisTextColorThe color of the Y axis text (this overrides the textColor option)null
yaxisTextBoldWhether the Y axis text is bold or not (this overrides the textColor option)null
yaxisTextItalicWhether the Y axis text is italic or not (this overrides the textItalic option)null
yaxisTextFontThe font of the Y axis text (this overrides the textFont option)null
yaxisTextSizeThe size of the Y axis text (this overrides the textSize option)null

Text

PropertyDescriptionDefault
textColorThe color of the text.black
textFontThe font used for text.sans-serif
textSizeThe size of the text.12
textBoldWhether the text is bold or not.false
textItalicWhether the text is italic or not.false

Line

PropertyDescriptionDefault
lineThis can either be a boolean or an array of booleans that determines whether a line is drawn connecting the points (for each dataset).false
lineColorsThis can either be a string or an array of strings that determines the colors of the lines that are drawn.black
lineLinewidthThis can either be a number or an array of numbers that determines the colors of the lines that are drawn.black

Key

PropertyDescriptionDefault
keyAn array of the labels that appear on the key.null
keyColorsAn array of colors to be shown on the key. If not specified then the colors option will be used instead.null
keyTextBoldWhether the key text is bold or not.false
keyTextFontThe font to use for the key text. If not specified it defaults to the textFont setting.null
keyTextSizeThe size to use for the key text. If not specified then the textSize is used.null
ketTextItalicWhether the key text is italic or not.false
keyTextOffsetxThe horizontal pixel offset of the key text (just the text).0
keyTextOffsetyThe vertical pixel offset of the key text (just the text).-1
keyOffsetxThe horizontal pixel offset of the entire key.0
keyOffsetyThe horizontal pixel offset of the entire key.0

Tooltips

PropertyDescriptionDefault
tooltipsOverrideIf required, this can be a function that totally handles the tooltip showing instead of the default RGraph tooltips. It should look like this:
tooltipsOverride: function (obj, opt)
{
    // Show tooltip
}
The opt is an argument that contains these items:
  • object The chart object.
  • index The index of the element (that triggered the tooltip).
  • sequentialIndex The sequential index of the element that was clicked.
  • text The text to be used as the tooltip. Remember that this may contain HTML (or whatever else you may have specified).
  • event The event object (either a click or mousemove event).
null
tooltipsCssClassThe CSS class thats applied to the tooltip DIV.RGraph_tooltip
tooltipsEventThe event used for tooltips (either click or mousemove.click
highlightFillThe fill color that's used when highlighting the chart.rgba(255,255,255,0.7)

Title

PropertyDescriptionDefault
titleThe title of the chart.(An empty string)
titleXThe specific X coordinate of the title.null
titleYThe specific Y coordinate of the title.null
titleHalignThe horizontal alignment of the title.center
titleValignThe vertical alignment of the title.bottom
titleColorThe color of the title.black
titleFontThe font used to render the title.null
titleSizeThe size of the font used to render the title.16
titleBoldWhether the title is bold or not.false
titleItalicWhether the title is italic or not.false
titleSubtitleThe subtitle of the chart. If a subtitle is specified the title is moved up to accommodate it. As such you might need to give a larger gutterTop value.(An empty string)
titleSubtitleXThe specific X coordinate of the subtitle.null
titleSubtitleYThe specific Y coordinate of the subtitle.null
titleSubtitleHalignThe horizontal alignment of the subtitle.center
titleSubtitleValignThe vertical alignment of the subtitle.top
titleSubtitleColorThe color of the subtitle.#aaa
titleSubtitleFontThe font used to render the subtitle.null
titleSubtitleSizeThe size of the font used to render the subtitle. It defaults to be the same as the textSize setting.10
titleBoldWhether the subtitle is bold or not.false
titleSubtitleItalicWhether the subtitle is italic or not.false

 

Methods

 

obj.set(name, value)

This can be used to set properties if necessary. It's normally used after the chart is drawn if you need to set additional parameters or change them.

 

obj.getYCoord(value)

This method can be used to get an appropriate X coord for a value when you're doing custom drawing on the chart. It returns null if the value is out of range.

 

obj.on(event, handler)

This function adds an event listener (such as onbeforedraw or ondraw) to the chart object.

 

obj.exec(func)

This function simply executes the function that you give it (there and then - not on any particular event)

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