4 columns: x y xdelta ydelta 6 columns: x y xlow xhigh ylow yhigh
The box width and height are determined from the x and y errors in the same way as they are for the xyerrorbars style — either from xlow to xhigh and from ylow to yhigh, or from x-xdelta to x+xdelta and from y-ydelta to y+ydelta, depending on how many data columns are provided.
The 6 column form of the command provides a convenient way to plot rectangles with arbitrary x and y bounds.
An additional (5th or 7th) input column may be used to provide variable (per-datapoint) color information (see linecolor and rgbcolor variable).
The interior of the boxes is drawn according to the current fillstyle. See set style fill and boxes for details. Alternatively a new fillstyle may be specified in the plot command.
Copyright 1986 - 1993, 1998, 2004 Thomas Williams, Colin Kelley
Distributed under the gnuplot license (rights to distribute modified versions are withheld).