This blog addresses the initial design for the line chart pattern in PatternFly. We are specifically interested in finding out expectations for interactions.
* How would you expect the user to interact with the line chart?
* How would you expect the info tip to behave?
Please leave comments with any questions or suggestions you may have!
The most common use case for line charts is to compare several data sets, or to show data over a period of time.
Multiple lines on the same chart allow the user to visualize relationships between varying data sets, such as correlated events, similarities or unexpected differences. We recommend displaying no more than 6 lines on a single graph to avoid confusion.
Axis Labels & Tick Marks
When the use case is visualizing data over a period of time, the horizontal axis represents time values and the vertical axis represents values. Axis labels are typically shown on both axis, and have associated major tick marks. Minor tick marks are a useful tool for the user to be able to estimate values.
Horizontal grid lines are recommended, since they help the user visualize the value. Vertical grid lines are unnecessary when visualizing data over a period of time.
For recommendations on line colors, see the PatternFly Color Palette. Points can optionally be shown to represent the data points on the line.
We suggest that an info tip be shown, including the time value associated with the data points along with each series name and data point
Some applications may allow the user to perform actions associated with a line. In this case, rIght clicking on a line could bring up a contextual menu with associated actions.
Zooming in and out within the chart could be accomplished with a mouse or by changing a an associated time filter. This topic will not be covered in the initial round of design.
PatternFly legends have already been discussed in both the Donut Chart and Bar Chart conceptual design and
In the initial round of design, we are not covering these topics:
* Handling missing data points
* Handling outlier data points