display very small numbers at axis

michael.kuettner · Post by **michael.kuettner** » Thu Jul 17, 2008 2:58 pm

I want to display very small numbers (downto 10e-20). If values get lower that 10e-6 only 0.000000 is displayed at axis. Is it possible to display scientific numbers (using ..e.. ) at the charts axis?

RoyW · Post by **RoyW** » Thu Jul 17, 2008 4:02 pm

You can use setNumberFormatOverride()

Code: Select all

        axis.setNumberFormatOverride(new DecimalFormat("00.0E0"));

And then create the DecimalFormat that you want.

michael.kuettner · Post by **michael.kuettner** » Fri Jul 18, 2008 7:46 am

This works for numbers greater than about 10e-7. For lower values the same thing happens: 00.0E0 is displayed. It can also happen that just nothing is displayed at the axis if i zoom in a little bit more.

Is there any rounding issue? Can i force the chart to use full double precision?

michael.kuettner · Post by **michael.kuettner** » Fri Jul 18, 2008 8:06 am

This is an example xy series i want to display (current over temperature):

Code: Select all

-40.0, 1.29233E-11
-40.0, 1.52194E-11
-40.0, 1.31989E-11
-40.0, 1.29233E-11
-40.0, 1.52194E-11
-40.0, 1.31989E-11
25.0, 1.93595E-11
25.0, 1.96145E-11
25.0, 1.9452E-11
25.0, 1.93595E-11
25.0, 1.96145E-11
25.0, 1.9452E-11
25.0, 1.93595E-11
25.0, 1.96145E-11
25.0, 1.9452E-11
25.0, 1.93595E-11
25.0, 1.96145E-11
25.0, 1.9452E-11
25.0, 1.93595E-11
25.0, 1.96145E-11
25.0, 1.9452E-11

Post by **david.gilbert** » Fri Jul 18, 2008 8:49 am

This is something that needs fixing in the default case. For a workaround, try axis.setStandardTickUnits(new StandardTickUnitSource()). Or add some appropriate tick sizes to the tick unit collection used by the axis.

michael.kuettner · Post by **michael.kuettner** » Fri Jul 18, 2008 9:16 am

Using axis.setStandardTickUnits(new StandardTickUnitSource()) works fine!
Thanks for the quick answer!