Is there any possibilities for interpolation

[Lanto]

Hi all,

I'm just discovering JFreeChart, and I'd like to say that it's a very powerful library.
I have a question on its possibilities : is there some classes/methods for polynomial interpolation, and of course drawing it in my graph ? Can JFreeChart do it ? If not, is it planned for future versions ?

Thanks,
Lanto

[David Gilbert]

Hi Lanto,

Do you mean fitting a polynomial function to a set of data points? There's no support for that, although there is a small framework in the com.jrefinery.data.Regression class for fitting curves to data points...that could probably be extended.

Regards,

Dave Gilbert

[Lanto]

Hi Dave,

That's exactly what I need : I have a set of points, and I'd like to draw a polynomial function (like f(x)=ax^2+bx+c) which represents an (approximative) interpolation for this set.
I think com.jrefinery.data.Regression class could help me, and probably com.jrefinery.data.Function2D too

Regards,

Lanto

[Guest]

I also want to fit a data set with a "best fit curve" drawn over the top of it.

[david.gilbert]

I also want to fit a data set with a "best fit curve" drawn over the top of it.

For those that have bought a copy of the JFreeChart Developer Guide, there is a "bonus" demo download containing a few extra demos...one of them shows how to use the Regression class to fit a linear regression line and a "power" regression line to some data and display them on a chart.

Regards,

Dave Gilbert

[phred]

For those that have bought a copy of the JFreeChart Developer Guide, there is a "bonus" demo download containing a few extra demos...one of them shows how to use the Regression class to fit a linear regression line and a "power" regression line to some data and display them on a chart.

could you post the sample picture in here? That'd be great..

[david.gilbert]

Here is the linear regression example:



...and here is the power regression example: