Create a chart in Django

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 interactivity, like, time navigator, date range selectors, tooltips with crosslines, interactive legend and more features, which enhance the experience of exploring and understanding time series data.

We have built a simple FusionCharts Django wrapper, which provides bindings for FusionTime. The FusionCharts Django wrapper allows you to easily add interactive time-series charts to any Django project.

Installation

In this section, we will show you how to install FusionCharts Suite XT and the FusionCharts Django wrapper along with all the other dependencies on your system.

Requirements

To create a chart in a web app developed using Django, download the following wrappers and frameworks in your system:

• Django Framework - Link
• FusionCharts Library - Link
• FusionCharts Django wrapper - Link

Note that the FusionCharts Django wrapper requires Python 2.7 or higher.

Step 1: Create a project

To create a project, follow the steps given below:

• Open the command prompt and run cd command to navigate to the required directory.

• Run the following command to create a myproject directory in your preferred directory.

django-admin startproject myprojectCOPY

Step 2: Add the dependencies

Now, we will add Django wrapper and FusionCharts JavaScript files required to render the charts in the web application. Steps to add the files are given below:

• Create a template folder inside the myproject directory.

• Inside the template folder, create another folder named static.

• Copy and paste the fusioncharts.py file from integrations > django > fusioncharts-wrapper in your project folder (myproject).

• Copy all JavaScript files extracted from the downloaded FusionCharts library into the template/static folder.

• Now, map the JavaScript files by creating an HTML file, index.html in the template folder. Include the fusioncharts.js and fusioncharts.timeseries.js using <script> tags from the downloaded package in this file.

{% load static %}
// Include FusionCharts core file
<script type="text/javascript" src="https://cdn.fusioncharts.com/fusioncharts/latest/fusioncharts.js"></script>
// Include FusionTime file
<script type="text/javascript" src="https://cdn.fusioncharts.com/fusioncharts/latest/fusioncharts.timeseries.js"></script>
COPY

{% load static %}
// Include FusionCharts core file
<script type="text/javascript" src="{% static "fusioncharts/latest/fusioncharts.js" %}"></script>
// Include FusionTime file
<script type="text/javascript" src="{% static "fusioncharts/latest/fusioncharts.timeseries.js" %}"></script>
COPY

After including the paths of all the dependencies required, update the static files by running the following command:

Python manage.py collectStaticCOPY

In the settings.py file, update the location of the templates:

'DIRS': ['myproject/templates']COPY

Create Your First Chart

Now that you have installed FusionTime and FusionCharts Django wrapper, let us build the first chart to show the Daily sales of a grocery store.

The chart will look as shown below:

The data for the above chart is shown in the table below:

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

• schema - which defines the properties of the columns.

• data - 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.

Next, 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 in the DataTable.

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:

• 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 about date formats, click here.

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

Create the data

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:

[
    [
        "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.

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

In the above code:

• 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

Once you have the data and the schema ready, create a .py file and copy the following code:

from ..fusioncharts import FusionCharts
from ..fusioncharts import FusionTable
from ..fusioncharts import TimeSeriesCOPY

In the above code, you can see how to include the fusioncharts.py file and import the classes, which have the functions needed to embed the charts in an HTML page.

Basic code to render a chart:

fusionTable = FusionTable(schema, data)
timeSeries = TimeSeries(fusionTable)

# Wrapper constructor parameters
# charttype, chartID, width, height, renderAt, data format, TimeSeries object

fcChart = FusionCharts("timeseries", "MyFirstChart" , "700", "450", "chart-container", "json", timeSeries)

# Returning complete JavaScript and HTML code, which is used to generate chart in the browsers.
return render(request,'index.html', {'output':fcChart.render()})COPY

In the above code:

• The following parameter values have been set for the chart wrapper constructor:

  • Value of charttype has been set to timeseries.

  • Value of chartID has been set to MyFirstChart.

  • Value of width has been set to 700.

  • Value of height has been set to 450.

  • Value of renderAt has been set to chart-container.

  • Value of data format has been set to json.

  • Value of the time-series object has been set to timeSeries.

• The render() member function of the FusionCharts wrapper has been used to render the chart.

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