The boxwidth command is used to set the default width of boxes in the boxes, boxerrorbars, candlesticks and histograms styles.
Syntax:
set boxwidth {<width>} {absolute|relative}
show boxwidth
By default, adjacent boxes are extended in width until they touch each other. A different default width may be specified using the boxwidth command. `Relative` widths are interpreted as being a fraction of this default width.
An explicit value for the boxwidth is interpreted as being a number of units along the current x axis (`absolute`) unless the modifier `relative` is given. If the x axis is a log-scale (see `set log`) then the value of boxwidth is truly "absolute" only at x=1; this physical width is maintained everywhere along the axis (i.e. the boxes do not become narrower the value of x increases). If the range spanned by a log scale x axis is far from x=1, some experimentation may be required to find a useful value of boxwidth.
The default is superseded by explicit width information taken from an extra data column in styles boxes or boxerrorbars. In a four-column data set, the fourth column will be interpreted as the box width unless the width is set to -2.0, in which case the width will be calculated automatically. See boxes and boxerrorbars for more details.
To set the box width to automatic use the command
set boxwidth
or, for four-column data,
set boxwidth -2
The same effect can be achieved with the using keyword in `plot`:
plot 'file' using 1:2:3:4:(-2)
To set the box width to half of the automatic size use
set boxwidth 0.5 relative
To set the box width to an absolute value of 2 use
set boxwidth 2 absolute