Using a range bar chart and visualizing a project schedule (Gantt like chart)
1. Overview
The Range Bar chart is a bar chart that displays bars for each dimension (category), ranging between a start value and an end value. For example, Range Bar charts can be used to represent the beginning and end of operations/tasks along a time axis, similar to a Gantt chart, for tracking project schedule. This article demonstrates a few Range Bar chart configurations that can be used in order to visualize measurement ranges, tasks, and project schedules.
2. Creating a Range Bar chart
A range bar chart has at least two measures (to be used as the start and end of the range bars) and one hierarchy. For example, in the following chart, the measures represent low and high temperatures for a day and work as a range of temperature values.
3. Showing task schedules and dependencies
A project can have multiple phases, such as Planning, Design, Implementation, etc. Each phase can have milestones and dependencies. You can use a Range Bar chart to show these milestones and their dependencies within a project phase.
3.1. Data preparation
The following table is used to create the chart. It has five milestones (M1, M2, etc.) and their timelines from the Design phase of a project. M3 is dependent on M2 and M5 is dependent on M4.
3.2. Creating the chart
Re-Visualize the table into a Range Bar chart.
Click Horizontal Bars from the toolbar.
Since the range bar series will be created using start and end dates instead of two measures, you may need to configure the Data Analysis Panel Visualization settings accordingly:
Also, make sure that you have the appropriate hierarchy as your axis.
Set the scale type for the bottom axis to Date/Time.
For this chart, check the Skip Missing Data under Bottom Axis (Bottom Axis 1) -> Axis -> Intervals in order to show only the dates available in the series.
3.3. Indicating task dependencies
There are multiple ways to indicate dependencies among tasks. A suitable option is to make use of states and creating state styles to indicate dependencies. There must be at least one measure in the metric set to be able to create states. The table is updated accordingly:
Follow the steps in the previous section to display the project schedule. When the Range Bar chart is ready, continue as follows:
Create a state group named Dependencies and add the following states:
You can add conditions in the Configure State dialog to compare hierarchy values. See the article setting up states on a metric set for the details on how to do so.
Add styles to the states.
Create three point styles. For each style, set the corresponding State and the Fill color.
As an additional step, you can show connecting lines between tasks to indicate the tasks that are supposed to run in sequence. To do that, navigate to Properties -> Main -> Data Point Series (Series 1) -> Look -> Connecting Lines and set the value to Bridge.
This will show multiple lines connecting M2 to M3 and M4 to M5, indicating the task sequence.
4. Showing the project schedule for multiple projects
You can use a Range Bar chart to display a schedule with multiple projects, along with their phases.
4.1. Data preparation
The following table is used to create the chart. It shows several project phases along with the start date and end date for each project.
4.2. Creating the chart
Re-Visualize the table into a Range Bar chart.
Click Horizontal Bars from the toolbar.
Make sure that the Visualization tab of the Data Analysis Panel has the following settings:
Under Series Layout, set the value of Custom Side-By-Side Position is to 1.
Set the scale type for the bottom axis to Date/Time. For this chart, Skip Missing Data is checked and Interval Method is set to Show Data Point Values under Bottom Axis (Bottom Axis 1) -> Axis -> Intervals in order to show only the dates available in the series.
5. Miscellaneous
5.1. Adding a line to indicate the current date
Often there is a requirement to show a vertical line in the chart to indicate the current date. This is useful to highlight where the project schedule stands. In the example shown above, you can add another metric set to the same chart using the Data Analysis Panel. In the following example, the dimension Now has the current date.
This will create a new series for the chart. For the series, set the Chart Type to Line. In the Visualization tab, add the dimension to Line Horizontal Position.
This will show the current date as a vertical line.
5.2. Adding milestone dates
You may want to show the milestone dates of each phase within a project timeline. Assume that you have the following chart:
You can add another metric set using the Data Analysis Panel to create a new series and set the Chart Type for the series to a Point chart.
The Visualization tab should have the following settings:
For the newly created series, navigate to the series properties and set the Marker Fill to White and the Marker Shape to Diamond. Now you can see the milestone dates along the project timeline for each project. You can use states and state styles for the point chart to illustrate the status of the milestones (i.e. In-progress, Delayed, Completed, etc.).
You can also make use of notes to record and show further details about the project milestones.