set label <label number> '<text>' [<co-ordinate>] <x>, [<co-ordinate>] <y> [rotate <angle>] [with colour <colour>]
<co-ordinate> = ( first | second | screen | graph | axis<axisnumber> )
The set label command can be used to place text labels onto a plot. For example:
set label 1 'Hello' 0, 0
would place the word ‘Hello’ at plot co-ordinates , as measured on the
- and
-axes. The tag 1 immediately following the label keyword is an identification number, and allows the label to be removed later with the unset label command. By default the position co-ordinates of the label are measured relative to the first
- and
-axes, but can be specified in a range of co-ordinate systems. These are specified as follows:
set label 1 'Hello' first 0, second 0
As can be seen, the name of the desired co-ordinate system precedes the position value in that co-ordinate system. Following Gnuplot’s nomenclature, the co-ordinate system first the default, measures the graph using the - and
-axes. second uses the
- and
-axes. screen and graph both measure in centimetres from the origin of the graph. The syntax axisn may also be used, to use the
th
- or
-axis; for example, axis3:
set label 1 'Hello' axis3 1, axis4 1
A rotation angle may optionally be specified after the keyword rotate to produce text rotated to any arbitrary angle, measured in degrees counter-clockwise. The following example would produce upward-running text:
set label 1 'Hello' 1.2, 2.5 rotate 90
By default the labels are black; however, an arbitrary colour may be specified using the with colour modifier. For example:
set label 3 'A purple label' 0, 0 with colour purple
will place a purple label at the origin.