Time Series BAR Charts

[Amit]

Currently the createTimeSeriesChart draws only an XY plot.
Is there a way I can get the "Time usage" but in a bar chart.
The advantage of the Time usage is that the dates are compressed with increase in the data.

Thanks

[Justin Johnson]

You can create an VerticalXYBarRenderer and add it to the plot.

TimeSeriesCollection dataset = new TimeSeriesCollection();
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.
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XYItemRenderer renderer = new VerticalXYBarRenderer(0.20);
XYPlot plot = new XYPlot(dataset, null, null, renderer);

[Amit]

Question on your recommendation .... how do I add my variables to the TimeSeriesCollection ?
I have the dates and some numbers for each date.

Thanks

[Justin Johnson]

Amit,

Create a BasicTimeSeries based on some unit of time (Second, Minute, Hour, Month, ...) and add your data points to it. Then add the BasicTimeSeries to your TimeSeriesCollection. I did something like this where I looped through the data and converted each date into a Second, then added it to the BasicTimeSeries. Then created the renderer like I described above and added my TimeSeriesCollection to it.

import com.jrefinery.data.Second;

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.
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TimeSeriesCollection availableDataset = new TimeSeriesCollection();
BasicTimeSeries available = new BasicTimeSeries("Available Licenses", Second.class);

available.add(mySecond, some_value);

availableDataset.addSeries(available);

[Amit]

My case is os dates (YYYY-MM-DD) .... there is not date type for that.

In your case, you are converting the dates into seconds.
But there are 2 potential problems with that.
1. You lose the feel of date ... as you are recoding them to seconds.
2. If the seconds range from 0 to 60 (not sure of that though), then you have a limited amount of data to work with.

Thanks

[Justin Johnson]

The time period just has to be unique so that all your data points can be displayed. It doesn't have to do with the format of the date that appears. I chose Second because I knew I would never have more than one data item per second, but I could potentially have multiple data items per minute, so Minute would not work for me. If you only have one data entry per year, use Year. Does that make sense?

[Amit]

Thanks Justin, I was able to create the bar chart. But got into a new problem now, Is there a way I can paint the Bars differently. Ex all the Bars on weekends, should be of a different color.

Thanks

[Justin Johnson]

Try

plot.setSeriesPaint(0, new Color(51, 153, 255));

or some other color and series number.

[Amit]

There is another problem that I am encountering now.
How do I plot time in case of StackedBar Charts ?
Or in case of Bar charts that have 6 bars (Categories) per day ?

Thanks