How to find probability of an interval using the density plot?

Dear all,

Given: d=randi([-3 3],10,1);% an arbritrary set of values U=[-5:5];%range of interest

Find: The images (probabilities) of the density plot for elements U as argument(values on x-axis).

From you matlab site I found nice instructions referring to the APP: Distribution fitting tool, and I manage to draw the density plot with a non-parametric distribution. I also generated the code, from which I understand 50%.

What I do not yet understand is how to find the probabilities (areas under density plot) for a set of values/ranges on the x-axis. For example, [-5,-4>, [-4,-3>........

Can anyone give me some feedback/suggestions?

Thank you in advance