plot probability density function of 2d data

Hi!

I need to find if the parameters in a 2D matrix (as in case of an image) are in normal form or not. I hence want to know how to plot the probability density function of the image as well as perform the KS test.

Answer 1

[the cyclist]

You don't provide much detail, but as a start maybe you could look at the hist() function for plotting, and the kstest() function for Kolmogorov-Smirnov test. You might also be interested in ksdensity() function.

[Rashi]

yeah..but I actually want to ascertain whether the points on an image follow a particular distribution or not.

[Image Analyst]

Do you mean that the values of the image follow a certain shape, like it would look like a Gaussian if you were to display it with the surf() function, OR do you mean that the distribution of the intensity values is a Gaussian, for example a flat, relatively uniform image with some small amount of noise superimposed on those uniform gray levels? If you mean the latter, then hist() will get you the distribution.