Modifying the contour plot from ksdensity

Hello,

I am trying to modify the 2D contour figure automatically generated by ksdensity for my bi-variate data.

I used the following lines, where ``data`` is a matrix size of 16000-by-2:

>> ksdensity(data,'PlotFcn','contour');

I used ``gcf``, ``gca``, ``findobj`` to extract the current figure, axis, object, however, I couldn't modify any of the properties I need. For example, setting it to a filled contour ('fill', 'on'), turning off the lines ('Linestyle','none') and increasing the level.

Does anyone know how to do this? Thanks!

Answer 1

[Samatha Aleti]

Hi,

As you are directly plotting using “ksdensity” function, you may not be able to change properties of plot. Instead of that, you may get the probability density estimate “f” (let) using “ksdensity” function and then plot separately. By doing this, you can use the plot object to change the properties as you need.

Below is the syntax:

[M,c] = contour( f );  
c.LineStyle = '-.' ; 

Refer the following documentation links for further details:

ksdensity

contour

[J T]

Hi Samatha,

So I obtained ``f`` from the following command where ``data`` is a two-column matrix (16000-by-2 in my case) and attempted to do what you mentioned above:

[f,x] = ksdensity(data,'function','pdf');
contour(f);

It didn't work because ``f`` is a vector size of (900-by-1), do you know how I could have ``ksdensity`` to return a field that could be passed on for contour plot?