n3-line-chart

n3-line-chart makes creating beautiful charts for AngularJS applications easy and semantic. It is built on top of D3.js.

You can find examples on the demo page.

How to install

• Install using bower : bower install n3-line-chart (or copy line-chart.min.js wherever you want)
• Reference line-chart.min.js in your index.html file
• Reference the module in your app file :

  angular.module('myApp', ['n3-line-chart'])
  

The module was originally named n3-charts.linechart. This is still valid but will probably be removed in the future.

How to use

A line chart is called using this syntax :

<linechart data="data" options="options" mode="" width="" height=""></linechart>

The line chart directives needs two attributes : data and options. If one is missing, nothing happens.

Data

Your data should look like this :

$scope.data = [
  {x: 0, value: 4, otherValue: 14},
  {x: 1, value: 8, otherValue: 1},
  {x: 2, value: 15, otherValue: 11},
  {x: 3, value: 16, otherValue: 147},
  {x: 4, value: 23, otherValue: 87},
  {x: 5, value: 42, otherValue: 45}
];

Please make sure it's sorted by abscissa.

Options

Options must be an object with a series array. It should look like this :

$scope.options = {
  axes: {
    x: {key: 'x', ticksFormat: '.2f', type: 'linear', min: 0, max: 10, ticks: 2},
    y: {type: 'linear', min: 0, max: 1, ticks: 5},
    y2: {type: 'linear', min: 0, max: 1, ticks: [1, 2, 3, 4]}
  },
  margin: {
    left: 100
  },
  series: [
    {y: 'value', color: 'steelblue', thickness: '2px', type: 'area', striped: true, label: 'Pouet'},
    {y: 'otherValue', axis: 'y2', color: 'lightsteelblue', visible: false, drawDots: true, dotSize: 2}
  ],
  lineMode: 'linear',
  tension: 0.7,
  tooltip: {mode: 'scrubber', formatter: function(x, y, series) {return 'pouet';}},
  drawLegend: true,
  drawDots: true,
  hideOverflow: false,
  columnsHGap: 5
}

Axes

The axes keys can be undefined. Otherwise, it can contain an x̀ key with the following properties :

• key : optional, defines where the chart will look for abscissas values in the data (default is 'x').
• type : optional, can be either 'date' or 'linear' (default is 'linear'). If set to 'date', the chart will expect Date objects as abscissas. No transformation is done by the chart itself, so the behavior is basically D3.js' time scale's.
• ticksFormat : optional, format string, that is parsed with d3.format (d3.time.format for type 'date') to format the axis' ticklabels. Default behavior: the raw value is used unformatted
• ticksFormatter : optional, function that allows to format the axis' ticklabels; must be a function that accepts a single argument and returns a string.
• tooltipFormat : optional, format string, that is parsed with d3.format (d3.time.format for type 'date') to format the axis' tooltip values (tooltip mode 'axes'). Default behavior: uses the same format as ticksFormat
• tooltipFormatter : optional, function that allows to format the axis' tooltip values (tooltip mode 'axes'); must be a function that accepts a single argument and returns a string.
• ticksRotate : optional, defines the rotation of the tick labels in degrees (positive values rotate clockwise, and negative vales counter clockwise)
• min : optional, forces the axis minimum value (default is computed from data)
• max : optional, forces the axis maximum value (default is computed from data)
• ticks : optional, configures the axis' ticks (can be either a number or an array, more on this here)
• ticksInterval : optional, configures the step size of tick values if ticks is set to a range or time range function (e.g. d3.time.minute), more on this here

It can also contain, according to your series configuration, a y and a y2 key with the following properties :

• type : optional, can be either linear' or 'log' (default is 'linear'). If set to 'log', the data may be clamped if its computed lower bound is 0 (this means the chart won't display an actual 0, but a close value - log scales can't display zero values).
• min : optional, forces the axis minimum value (default is computed from data)
• max : optional, forces the axis maximum value (default is computed from data)
• width : optional, forces the axis width (default is 50)

Series

The series key must be an array which contains objects with the following properties :

• y : mandatory, defines which property on each data row will be used as ordinate value.
• color : optional, any valid HTML color (if none given, the chart will set it for you).
• label : optional, will be used in the legend (if undefined, the y value will be used).
• axis : optional, can be either 'y' (default, for left) or 'y2' (for right). Defines which vertical axis should be used for this series. If no right axis is needed, none will be displayed.
• type : optional, can be one value between 'line', 'area', 'column'. Default is 'line'.
• striped : optional, can be either true or false. Default is false. Will be ignored if the series type is not 'area'.
• thickness : optional, can be {n}px. Default is 1px. Will be ignored if the series type is not 'area' or 'line'.
• lineMode : optional, can be dashed. Default is undefined. Defines whether the series is rendered as a dashed line. Removed if the series type is not line or area.
• drawDots : optional, can be either true or false. Default is true. Defines whether the series is rendered with dots on a per series basis. Overrides the global setting.
• visible : optional, can be either true or false. Default is true. Defines whether the series is initially visible. Will be updated if the series gets hidden or shown through a click on the legend.
• dotSize : optional, must be an numerical value. Default is 2. Will be ignored if the series type is not area or line, or if drawDots is set to false.

Tooltip

The tooltip must be an object which contains the following properties :

• mode : can be set to none, axes, or scrubber. It can also be set to scrubber, which displays tooltips for all series. Default is scrubber.
• interpolate : can be either trueor false. Default is false. Will be ignored if the tooltip's mode is not axes.
• formatter : optional, allows to catch the tooltip before it gets rendered. Must be a function that takes x, y and series as arguments and returns a string. Ignored when mode is not scrubber.

Margin

With the margin option one can customize the following margins of the chart :

• top
• left
• bottom
• right

Optional stuff

Additionally, you can set lineMode to a value between these :

• linear (default)
• step-before
• step-after
• basis
• basis-open
• basis-closed
• bundle
• cardinal
• cardinal-open
• cadinal-closed
• monotone

The tension can be set, too (default is 0.7). See issue #44 about that.

For more information about interpolation, please consult the D3.js documentation about that.

The drawLegend and drawDots are optional. They respectively enable/disable the chart's legend and the lines and areas dots. Default is true for both.

The columnsHGap is optional (default is 5). Sets the space between two columns. If you haven't any column series on your chart but are wondering why this option doesn't do anything, please don't send me an email.

If hideOverflow is set to true, the series will be clipped to the chart area to avoid displaying negative values for certain lineModes (e.g. cardinal). See issue #120 about that.

Mode

The mode can be set to 'thumbnail' (default is empty string). If so, the chart will take as much space as it can, and it will only display the series. No axes, no legend, no tooltips. Furthermore, the lines or areas will be drawn without dots. This is convenient for sparklines.

Width and height

This is more a hack. The chart usually tries to infer its own dimensions regarding its parent, but sometimes it fails like a noob. That's why these two attributes can be set. The should look like this :

<linechart width="150" height="100"></linechart>

Custom events

We can attach event handlers for click, hover, focus and toggle events of the chart.

Click

The event handler for the click event get's triggered when the mouse clicks on a dot or column of the chart in tooltip modes none and axes.

$scope.onClick = function(d, i){
  console.log(d, i);
}

<linechart data="data" options="options" on-click="onClick"></linechart>

Hover

The event handler for the hover event get's triggered when the mouse hovers over a dot or column of the chart in tooltip modes none and axes.

$scope.onHover = function(d, i){
  console.log(d, i);
}

<linechart data="data" options="options" on-hover="onHover"></linechart>

Focus

The event handler for a focus event get's triggered when the mouse hovers over the chart in tooltip mode scrubber.

$scope.onFocus = function(d, i, position){
  console.log(d, i, position);
}

<linechart data="data" options="options" on-focus="onFocus"></linechart>

Toggle

The event handler for a toggle event get's triggered when a series changes its visibility.

$scope.onToggle = function(d, i, visible){
  console.log(d, i, visible);
}

<linechart data="data" options="options" on-toggle="onToggle"></linechart>

Building

Fetch the repo :

$ git clone https://github.com/n3-charts/line-chart.git

Install dev dependencies :

$ npm install

Install components :

$ bower install

Watch :

$ grunt watch

Or just build :

$ grunt

Or run the visual tests, too :

$ grunt travis

Contributing

You're welcome to submit issues and PRs. However, please make sure :

• to link a CodePen/Plunker/JSFiddle with your issue (you can generate CodePens from the examples page, clickhover any example and a link will appear in the example's top right corner)
• to add tests to your pull requests (otherwise, a ruthless admin will inevitably close your pull request)

Testing

AngularJS is designed to build testable apps, so is this project. It has a good coverage rate (above 95%), let's keep it this way.