Filledcurves

The filledcurves style is only used for 2D plotting. It has three variants. The first two variants require either a single function or two columns (x,y) of input data, and may be further modified by the options listed below.

Syntax:

plot ... with filledcurves [option]

where the option can be one of the following

[closed | {above | below}
{x1 | x2 | y | r}[=<a>] | xy=<x>,<y>]

The first variant, closed, treats the curve itself as a closed polygon. This is the default if there are two columns of input data.

The second variant is to fill the area between the curve and a given axis, a horizontal or vertical line, or a point.

filledcurves closed   ... just filled closed curve,
filledcurves x1       ... x1 axis,
filledcurves x2       ... x2 axis, etc for y1 and y2 axes,
filledcurves y=42     ... line at y=42, i.e. parallel to x axis,
filledcurves xy=10,20 ... point 10,20 of x1,y1 axes (arc-like shape).
filledcurves above r=1.5  the area of a polar plot outside radius 1.5

The third variant fills the area between two curves sampled at the same set of x coordinates. It requires three columns of input data (x, y1, y2). This is the default if there are three or more columns of input data. If you have a y value in column 2 and an associated error value in column 3 the area of uncertainty can be represented by shading. See also the similar 3D plot style zerrorfill.

3 columns:  x  y  yerror

plot $DAT using 1:($2-$3):($2+$3) with filledcurves, \
     $DAT using 1:2 smooth mcs with lines

The above and below options apply both to commands of the form

... filledcurves above {x1|x2|y|r}=<val>

and to commands of the form

... using 1:2:3 with filledcurves below

In either case the option limits the filled area to one side of the bounding line or curve.

Notes: Not all terminal types support this plotting mode.

The x= and y= keywords are ignored for 3 columns data plots

Zooming a filled curve drawn from a datafile may produce empty or incorrect areas because gnuplot is clipping points and lines, and not areas.

If the values <x>, <y>, or <a> are outside the drawing boundary they are moved to the graph boundary. Then the actual fill area in the case of option xy=<x>,<y> will depend on xrange and yrange.

Fill properties

Plotting with filledcurves can be further customized by giving a fillstyle (solid/transparent/pattern) or a fillcolor. If no fillstyle (fs) is given in the plot command then the current default fill style is used. See set style fill. If no fillcolor (fc) is given in the plot command, the usual linetype color sequence is followed.

The {{no}border} property of the fillstyle is honored by filledcurves mode closed, the default. It is ignored by all other filledcurves modes. Example:

plot 'data' with filledcurves fc "cyan" fs solid 0.5 border lc "blue"