gnuplot documentation

108 gnuplot 4.3 70 SET-SHOW
70.28.1 Key placement
To understand positioning, the best concept is to think of a region, i.e., inside/outside, or one of the
margins. Along with the region, keywords left/center/right (l/c/r) and top/center/bottom (t/c/b)
control where within the particular region the key should be placed.
When in inside mode, the keywords left (l), right (r), top (t), bottom (b), and center (c) push the
key out toward the plot boundary as illustrated:
t/l t/c t/r
c/l c c/r
b/l b/c b/r
When in outside mode, automatic placement is similar to the above illustration, but with respect to
the view, rather than the graph boundary. That is, a border is moved inward to make room for the
key outside of the plotting area, although this may interfere with other labels and may cause an error
on some devices. The particular plot border that is moved depends upon the position described above
and the stacking direction. For options centered in one of the dimensions, there is no ambiguity about
which border to move. For the corners, when the stack direction is vertical, the left or right border
is moved inward appropriately. When the stack direction is horizontal, the top or bottom border is
moved inward appropriately.
The margin syntax allows automatic placement of key regardless of stack direction. When one of the
margins lmargin (lm), rmargin (rm), tmargin (tm), and bmargin (bm) is combined with a single,
non-conflicting direction keyword, the following illustrated positions may contain the key:
l/tm c/tm r/tm
t/lm
c/lm
b/lm
t/rm
c/rm
b/rm
l/bm c/bm r/bm
Keywords above and over are synonymous with tmargin. For version compatibility, above or over
without an additional l/c/r or stack direction keyword uses center and horizontal. Keywords below
and under are synonymous with bmargin. For compatibility, below or under without an additional
l/c/r or stack direction keyword uses center and horizontal. A further compatibility issue is that
outside appearing without an additional t/b/c or stack direction keyword uses top, right and vertical
(i.e., the same as t/rm above).
The can be a simple x,y,z as in previous versions, but these can be preceded by one of five
keywords (first, second, graph, screen, character) which selects the coordinate system in which the
position of the first sample line is specified. See coordinates (p. 24) for more details. The effect of
left, right, top, bottom, and center when is given is to align the key as though it were
text positioned using the label command, i.e., left means left align with key to the right of ,
etc.
70.28.2 Key samples
By default, each plot on the graph generates a corresponding entry in the key. This entry contains a
plot title and a sample line/point/box of the same color and fill properties as used in the plot itself. The
font and textcolor properties control the appearance of the individual plot titles that appear in the key.
Setting the textcolor to "rgb variable" causes the text for each key entry to be the same color as the
line or fill color for that plot. This was the default in some earlier versions of gnuplot.
The length of the sample line can be controlled by samplen. The sample length is computed as the sum
of the tic length and times the character width. samplen also affects the positions of