# Place a boxplot at x coordinate 1.0 representing the y values in column 5 plot 'data' using (1.0):5
# Same plot but suppress outliers and force the width of the boxplot to 0.3 set style boxplot nooutliers plot 'data' using (1.0):5:(0.3)
By default only one boxplot is produced that represents all y values from the second column of the using specification. However, an additional (fourth) column can be added to the specification. If present, the values of that column will be interpreted as the discrete levels of a factor variable. As many boxplots will be drawn as there are levels in the factor variable. The separation between these boxplots is 1.0 by default, but it can be changed by set style boxplot separation. By default, the value of the factor variable is shown as a tic label below (or above) each boxplot.
# Suppose that column 2 of 'data' contains either "control" or "treatment" # The following example produces two boxplots, one for each level of the # factor plot 'data' using (1.0):5:(0):2
The default width of the box can be set via set boxwidth <width> or may be specified as an optional 3rd column in the using clause of the plot command. The first and third columns (x coordinate and width) are normally provided as constants rather than as data columns.
By default the whiskers extend from the ends of the box to the most distant point whose y value lies within 1.5 times the interquartile range. By default outliers are drawn as circles (point type 7). The width of the bars at the end of the whiskers may be controlled using set bars or set errorbars.
Copyright 1986 - 1993, 1998, 2004 Thomas Williams, Colin Kelley
Distributed under the gnuplot license (rights to distribute modified versions are withheld).