Histograms
The hist() function

R offers several functions producing histograms. First the hist() function: it has a number of options to produc different types of histograms. Note that the histogram will produce a gaphical window.

Refinements

Add a dotplot to a histogram:

hist(urb)
rug(urb)

rug() is one of the many functions that let you modify an existing graph, by adding further elements.

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