CODEWITHSUNDEEP
jfreechart
Eddie
Eddie

Reputation: 21

Create custom x-axis labels for line chart jfreechart

I created a line chart that displays time every 10 minutes on the x-axis. The data can be for a month long, so the x-axis labels are blended together (unreadable). Also, the grid lines are too close together. I need to figure out how to hide the x-axis chart labels and grid lines and create custom labels and grid lines to only show every hour (or maybe every month if I need to display the graph for a 6 month period). Currently, the x-axis labels are date time format. If 24 hour period is graphed, I need to only show the time every hour. If more than 1 month is graphed, I need to show the date.

Upvotes: 2

Views: 6180

Answers (2)

Jes
Jes

Reputation: 2778

The 10-minute ticks are way to much to display, instead you should either:

  • set the NumberAxis setAutoRange() to true
  • manually set the min, max and most importantly the TickUnit.

For dates and time go check out DateTickUnit, and for numbers in general it is NumberTickUnit

If you can determine what range is displayed, it is only a matter of creating the correct DateTickUnit. If it for example is hours: 

numberAxis.setTickUnit(new DateTickUnit(DateTickUnitType.HOUR, 1));

The gridlines you mention will be the same place as the tick marks so this should solve both problems.

Upvotes: 1

trashgod
trashgod

Reputation: 205785

Note that a month's data is 6 * 24 * 30 = 4320; that's too many values to view with much precision, and 6 moths is worse. As an alternative, you can slide or page the data set. The default axis labels should adjust automatically. If you have problems, please post an sscce.

Upvotes: 1

Related Questions