Gnuplot 图例 errorbar 符号垂直

Question

如何使用 gnuplot 使图例错误符号垂直而不是水平？ set key vertical 没有给出想要的结果：

set key vertical
plot "file.txt" using 1:2:3 with yerrorbars

Answer 1

^{感谢 by Christoph 的想法。}

如Christoph in comments on the question, there is no built-in way to change the orientation of the errorbars in the legend: xerrorbars, yerrorbars and xyerrorbars所示，都是水平的。

要获得垂直误差线，可以考虑禁用图例 (unset key) 并使用 set label 和 set arrow 手动绘制。即可以将误差条绘制为带有两个头的箭头，形状为垂直于箭头线的线。这可能看起来像：

# definition of arrow styles and line styles here, something like:
#   set style line 41 lc rgb "#cccccc" lt 1 lw 1 ps 0.5 pt 6
#   set style arrow 1 heads size screen 0.008,90 ls 1
#   ...

set label "class 1" at graph 0.7, graph 1                         # label
set arrow as 1  from graph 1, graph 0.97  to graph 1, graph 1.02  # arrow
set label ""    at   graph 1, graph 0.99  point ls 1              # dot

set label "class 2" at graph 0.7, graph 0.8                       # label
set arrow as 2  from graph 1, graph 0.77  to graph 1, graph 0.82  # arrow
set label ""    at   graph 1, graph 0.79  point ls 2              # dot

您当然可以调整条形的长度、它们的位置、点的大小、垂直线的长度，...

Gnuplot 图例 errorbar 符号垂直

Gnuplot legend errorbar symbol vertical

gnuplot

legend