newhistogram {"<title>"} {<linetype>} {<fillstyle>} {at <x-coord>}
More than one set of histograms can appear in a single plot. In this case you can force a gap between them, and a separate label for each set, by using the newhistogram command. For example
set style histogram cluster
plot newhistogram "Set A", 'a' using 1, '' using 2, '' using 3, \
newhistogram "Set B", 'b' using 1, '' using 2, '' using 3
The labels "Set A" and "Set B" will appear beneath the respective sets of histograms, under the overall x axis label.
The newhistogram command can also be used to force histogram coloring to begin with a specific color (linetype). By default colors will continue to increment successively even across histogram boundaries. Here is an example using the same coloring for multiple histograms
plot newhistogram "Set A" lt 4, 'a' using 1, '' using 2, '' using 3, \
newhistogram "Set B" lt 4, 'b' using 1, '' using 2, '' using 3
Similarly you can force the next histogram to begin with a specified fillstyle. If the fillstyle is set to `pattern`, then the pattern used for filling will be incremented automatically.
The `at <x-coord>` option only applies to column-stacked histograms.