Plots may be displayed in one of thirteen styles: lines, points, linespoints, impulses, dots, steps, fsteps, {x,y,xy}errorbars, boxes, boxerrorbars, or boxxyerrorbars. The lines style connects adjacent points with lines. The points style displays a small symbol at each point. The linespoints style does both lines and points. The impulses style displays a vertical line from the x axis (or from the grid base for splot) to each point. The dots style plots a tiny dot at each point; this is useful for scatter plots with many points.
The errorbars (or yerrorbars), xerrorbars, xyerrorbars styles are only relevant to 2-d data file plotting. It is treated like points for splots and function plots. For data plots, errorbars is like points, except that a vertical or horizontal error bar is also drawn: for each point (x,y), a line is drawn from (x,ylow) to (x,yhigh) or (xlow,y) to (xhigh,y). A tic mark is placed at the ends of the error bar. The (ylow, yhigh) or (xlow,xhigh) values are read from the data file's columns, as specified with the using option to plot. See plot errorbars for more information.
The boxes style is only relevant to 2-d plotting. It draws a box centred about the given x coordinate from the yaxis to the given y coordinate. The width of the box is obtained in one of three ways. If a data file has a third column, this will be used to set the width of the box. Otherwise, if a width has been set using the set boxwidth command, this will be used. Otherwise the width of each box will be calculated automatically so that it touches the adjacent boxes. Another style called boxerrorbars is also available and is only relevant to 2-d data file plotting. This style is a combination of the boxes and errorbars styles. The boxwidth will come from the fourth column if the y errors are in the form of ``ydelta'' and the boxwidth was not previously set equal to -2.0 ( set boxwidth -2.0) or from the fifth column if the y errors are in the form of ``ylow yhigh''. The boxwidth = -2.0 is for the special case of 4-column data and the y errors are in the form of ``ylow yhigh''. The boxwidth will be calculated automatically so that each box touches the adjacent boxes. The width will also be automatically calculated if 3-column data is used. The boxxyerrorbars style is like the xyerrorbars option except that a box with width (xhigh-xlow) and height (yhigh-ylow) is drawn instead of a cross of that size.
For 2-d data with more than two columns, gnuplot will be picky about the allowed plot styles. For three columns only xerrorbars, boxes, errorbars (or yerrorbars), and boxerrorbars are allowed. If another plot style is used, the style will be changed to yerrorbars. The boxerrorbars style will calculate the boxwidth automatically. For four columns only xerrorbars, xyerrorbars, boxxyerrorbars, boxerrorbars, and errorbars (or yerrorbars) are allowed. An illegal plot style will be changed to yerrorbars. Five column data allows only the boxerrorbars style. An illegal style will be changed to boxerrorbars before plotting. Six and seven column data only allows the xyerrorbars and boxxyerrorbars styles. Illegal styles will be changed to xyerrorbars before plotting. Use the using option for plot to setup the correct number of columns for the style you want.
The steps and fsteps styles is only relevant to 2-d plotting. The steps style connects consecutive points with two line segments: the first from (x1,y1) to (x2,y1) and the second from (x2,y1) to (x2,y2). The fsteps: (x1,y1) to (x1,y2) and (x1,y2) to (x2,y2).
Default styles are chosen with the set function style and set data style commands. See plot style for information about how to override the default plotting style for individual functions.
Syntax:
set function style <style>
set data style <style>
show function style
show data style
where <style> is lines, points, linespoints, impulses,
dots, steps, fsteps, {x,y,xy}errorbars, boxes, boxerrorbars,
or boxxyerrorbars.