Creating a histogram

Styles can alter the way data is presented in arbitrary ways. Here the
histogram style is used to generate a histogram. ... By default the histogram
draws a box for each histogram value, but you can set the `step` parameter of
the histogram style to use steps instead.

! In this basic use-case the histogram is calculated out of equal-spaced
x-values automatically. You can also use errorbar like data in one graph
dimension to generate histograms with different widths of the histogram boxes.

! Note that a histogram is very different from a bar graph in that it uses
regular axes (like the default linear axes in this example) in both graph
dimensions. Instead, bar graphs use a discrete axis.
