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javajfreechartexponentialyaxis

Exponential tick on linear yAxis - JFreeChart

I have a chart with a logarithmic yAxis like this one: logarithmic chart

As we can see, the yAxis have exponential ticks (I setted it that way with yAxis.setExpTickLabelsFlag(true);). Here is the same chart with a linear axis (the one by default when creating a xylineChart):

linear chart

Unfortunately, my values on the yAxis can't be formatted with exponential ticks because it is not a LogarithmicAxis. How can I force it to?

Solution

  • As shown here, you can invoke setNumberFormatOverride() to set the desired DecimalFormat. You can invoke the setExponentSeparator() method of DecimalFormatSymbols to set the desired exponent separator.

    DecimalFormatSymbols symbols = new DecimalFormatSymbols();
symbols.setExponentSeparator("e");
DecimalFormat format = new DecimalFormat("0.######E0", symbols);
yAxis.setNumberFormatOverride(format);

    Alternatively, you should be able to modify the numberFormatterObj of LogarithmicAxis in a custom implementation of setupNumberFmtObj(), seen here, but I haven't tried it.