One can fill histograms with data from vectors and matricies.
Here we create a vector with random numbers distributed using the Poisson statistics. Then we create a histogram with the title "Poisson", 20 bins, in the range between 1 and 10. Then we use draw2d() to display the histogram. You can access the descriptive statistics as for any vector or matrix.
Analogously, you can do similar calculations for matrices.