Create a Chart in Svelte

FusionTime is a JavaScript charting library that helps you visualize, and explore time-series data. In FusionTime, you get lots of out-of-the-box interactive features, such as time navigator, date range selectors, tooltips with crosslines, interactive legend and more. These features enhance the experience of exploring and understanding time-series data

We have built a simple svelte-fusioncharts component, which provides bindings for FusionTime. The svelte-fusioncharts component allows you to easily add interactive time-series charts in your Svelte application or project without any hassle.

In this page, we'll see how to install FusionTime and render an interactive time-series chart using the svelte-fusioncharts component.

Installation

Since FusionTime is distributed along with FusionCharts Suite, download/install the FusionCharts package to get access to FusionTime and other chart types of the FusionCharts Suite. To install follow the steps below:

Install svelte-fusioncharts and fusioncharts libraries with the following command:

npm install svelte-fusioncharts fusioncharts --saveCOPY

That completes the installation of FusionCharts and the svelte-fusioncharts directive.

Create Your First Chart

Let's create a time-series chart using svelte-fusioncharts component showing Daily sales of a grocery store.

The chart will look as shown below:

The data for the above chart is too big to be displayed here. The table below shows the sample data of the above chart:

FusionTime accepts a DataTable as the data source. DataTable is the tabular representation of data. To create the DataTable, you need to provide the following:

• schema - which defines the properties of the columns.
• data - which contains the values of each row and column of the DataTable.

For an instance of FusionTime, you can create n number of DataTables, but only one DataStore.

Now, let's learn how to prepare the schema and the data of the DataTable.

Create the schema

The schema outlines each column represented in the above table. The schema contains an array which has multiple objects created in it. Each object represents a column of the above table.

name and type are mandatory keys for each object. If the object type is time then format is also a mandatory key.

To define the schema, let's create a schema.json file and copy the following code:

It is not mandatory to create the schema in a different .json file. You can also define the schema within the .html file.

[
  {
    "name": "Time",
    "type": "date",
    "format": "%-m/%-d/%Y"
  },
  {
    "name": "Sales",
    "type": "number"
  }
]COPY

In the above code:

• schema is the variable in which the array is stored.
• Each object of a schema maps to a column of the tabular representation of the data.
• The JSON object has the following attributes:
  • name - Specify the name of the column of the tabular representation of data
  • type - Specify the type of the column.
  • format - Specify the input format of the date as per your data. In this example, the format is %-m/%-d/%Y. To know more on date formats click here.

Now that we have the schema ready, let's work on the data.

Create data

Data can be provided either in JSON format or 2D array format. We will use the 2D array format.

Data for the above chart is too big to be shown here. A sample of it has been used in the data object defined below:

var data = [
    [
        "1/4/2011",
        16.448
    ],
    [
        "1/5/2011",
        272.736
    ],
    [
        "1/5/2011",
        11.784
    ],
    [
        "1/5/2011",
        3.54
    ],
    [
        "1/6/2011",
        19.536
    ],
    [
        "1/7/2011",
        2573.82
    ],
]COPY

Create a new data.json file, and copy the above code there. Next, copy the entire data and replace it with the content of the data object in your 'data.json' file.

It is not mandatory to create a data.json file. You can also do the same in your HTML file.

In the above code:

• data is the variable in which the data array is stored.
• Each object in the data array corresponds to a row in the tabular representation of the data.
• Each element in an object is represented by each object of the schema. The values in each object of the array represent the following:
  • Time according to the format
  • Total sales amount

We are all set with our data to create the chart.

By default, FusionTime applies the average function to aggregate the data and display on the chart. You can change the aggregate function from average to any other numeric calculation. To know more, click here.

Now, let's create the files to render the above chart.

Render the chart

Finally, get ready to render your chart. In the .svelte file, import the fusioncharts dependencies and include the consolidated code shown below.

<script>
  import FusionCharts from 'fusioncharts';
  import Timeseries from 'fusioncharts/fusioncharts.timeseries';
  import SvelteFC, { fcRoot } from 'svelte-fusioncharts';

  fcRoot(FusionCharts, Timeseries);

  let promise,
    jsonify = res => res.json(),
    dataFetch = fetch(
      "https://s3.eu-central-1.amazonaws.com/fusion.store/ft/data/line-chart-with-time-axis-data.json"
    ).then(jsonify),
    schemaFetch = fetch(
      "https://s3.eu-central-1.amazonaws.com/fusion.store/ft/schema/line-chart-with-time-axis-schema.json"
    ).then(jsonify);

  promise = Promise.all([dataFetch, schemaFetch]);

  const getChartConfig = ([data, schema]) => {
    const fusionDataStore = new FusionCharts.DataStore(),
      fusionTable = fusionDataStore.createDataTable(data, schema);

    return {
      type: "timeseries",
      width: "100%",
      height: 450,
      renderAt: "chart-container",
      dataSource: {
        data: fusionTable,
        caption: {text: "Sales Analysis"},
        subcaption: {text: "Grocery"},
        yAxis: [
          {
            plot: {
              value: "Grocery Sales Value",
              type: "line"
            },
            format: {
              prefix: "$"
            },
            title: "Sale Value"
          }
        ]
      }
    };
  };
</script>
//Include the chart in the container
<div id="chart-container" >
    {#await promise}
        <p>Fetching data and schema...</p>
    {:then value}
    <SvelteFC
        {...getChartConfig(value)}
    />
    {:catch error}
        <p>Something went wrong: {error.message}</p>
    {/await}
</div>COPY

In the above code:

• Include the fusioncharts library in the .svelte file.
• Include data.json and schema.json files.
• Define the chart configuration in the FusionCharts constructor:
  • Set the type as timeseries.
  • Set the chart container as container using the renderAt property.
  • Set the width and height (in pixels).
  • Set the name of the DataTable as the value of the data property of dataSource.
  • Set the data to create the chart.
  • Specify the caption of the chart using text attribute in caption object.
• Create an empty storage as fusionDataStore using FusionCharts.DataStore.
• Create a DataTable within the empty storage using fusionDataStore.createDataTable and pass the schema and data to the DataTable.

You should be able to see the chart. If you are getting a JavaScript error on your page, check your browser console for the exact error and fix accordingly. If you're unable to solve it, click here to get in touch with our support team.

That's it! Your first chart in SvelteJS using FusionTime is ready.