我想使用groupplots库绘制几组数据pgfplots。在每个图上，我想添加一些其他数据，这些数据在各个图中不会发生变化。因此，我将绘图命令放在一个\foreach循环中，但我无法从描述这些额外数据的输入表中获取图例条目。我尝试了类似于使用表格的第一行作为 pgfplot 图中的图例条目？，但它无法编译（当第二次解析引用时它不喜欢\colname）。
下面是一个示例和输出。正确答案是将标签从“模型”重命名为列\modeltable。（如果水平方向上的标签间距再远一点就更好了……）
\documentclass[crop]{standalone}
\usepackage[svgnames]{xcolor}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\usepgfplotslibrary{groupplots}
\pgfplotsset{% global config
compat=newest,
every minor tick={very thin, gray},
minor tick num=4,
enlargelimits=0.02,
group style={
columns=2,
xlabels at=edge bottom,
ylabels at=edge left},
every axis legend/.append style={
legend cell align=left,
legend columns=4
}
}
\pgfplotstableread{
Time {Model A} {Model G} {Model Z}
0 1 1 1
1 1 2 2
2 2 3 3
3 3 4 4
4 5 5 8
5 8 6 10
6 13 7 16
}\modeltable
\pgfplotstableread{
Time {Data 1} {Data 2}
0 1.3 2.3
1 2.6 3.6
2 3.8 4.8
3 7.9 5.9
4 6.3 7.3
5 7.5 6.5
6 9.0 8.9
}\datatable
\begin{document}
\begin{tikzpicture}
\begin{groupplot}[
xlabel={Time},
ylabel={Amplitude},
every axis title shift=0,
legend to name=grouplegend]
\pgfplotsinvokeforeach{1,2}{%
\nextgroupplot[title=Data $#1$]
% Models
\foreach \y in {1, 2, 3} {
\addplot [smooth, dashed, color=DarkRed]
table[x index=0, y index=\y] {\modeltable};
%\pgfplotstablegetcolumnnamebyindex{\y}\of{\modeltable}\to{\colname}
%\addlegendentry {\colname}
\addlegendentry{Model}
}
% Data
\addplot [only marks, mark=o]
table[x index=0, y index=#1] {\datatable};
\addlegendentry {Data}
}
\end{groupplot}
\node (dummytitle) at ($(group c1r1.north)!0.5!(group c2r1.north)$)
[above]{};
\node (title) at (dummytitle.north)
[above, yshift=\pgfkeysvalueof{/pgfplots/every axis title shift}]
{Experimental Data};
\node (legend) at ($(group c1r1.south)!0.5!(group c2r1.south)$)
[below, yshift=-2\pgfkeysvalueof{/pgfplots/every axis title shift}]
{\ref{grouplegend}};
\end{tikzpicture}
\end{document}
答案1
默认情况下，使用 添加的条目不会展开，因此它们都只在调用图例时\addlegendentry组成，这超出了定义的范围。可以通过改用 来解决这个问题。\colname\colname\addlegendentryexpanded{...}
我还擅自在图例条目之间添加了一点空间（如如何调整 PGFPlots 中图例条目之间的水平间距？)：
\documentclass[]{standalone}
\usepackage[svgnames]{xcolor}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\usepgfplotslibrary{groupplots}
\pgfplotsset{% global config
compat=newest,
every minor tick={very thin, gray},
minor tick num=4,
enlargelimits=0.02,
group style={
columns=2,
xlabels at=edge bottom,
ylabels at=edge left},
every axis legend/.append style={
legend cell align=left,
legend columns=4
}
}
\pgfplotstableread{
Time {Model A} {Model G} {Model Z}
0 1 1 1
1 1 2 2
2 2 3 3
3 3 4 4
4 5 5 8
5 8 6 10
6 13 7 16
}\modeltable
\pgfplotstableread{
Time {Data 1} {Data 2}
0 1.3 2.3
1 2.6 3.6
2 3.8 4.8
3 7.9 5.9
4 6.3 7.3
5 7.5 6.5
6 9.0 8.9
}\datatable
\begin{document}
\begin{tikzpicture}
\begin{groupplot}[
xlabel={Time},
ylabel={Amplitude},
every axis title shift=0,
legend to name=grouplegend,
legend style={/tikz/every even column/.append style={column sep=0.5cm}}
]
\pgfplotsinvokeforeach{1,2}{%
\nextgroupplot[title=Data $#1$]
% Models
\foreach \y in {1, 2, 3} {
\addplot [smooth, dashed, color=DarkRed]
table[x index=0, y index=\y] {\modeltable};
\pgfplotstablegetcolumnnamebyindex{\y}\of{\modeltable}\to{\colname}
\addlegendentryexpanded{\colname}
}
% Data
\addplot [only marks, mark=o]
table[x index=0, y index=#1] {\datatable};
\addlegendentry {Data}
}
\end{groupplot}
\node (dummytitle) at ($(group c1r1.north)!0.5!(group c2r1.north)$)
[above]{};
\node (title) at (dummytitle.north)
[above, yshift=\pgfkeysvalueof{/pgfplots/every axis title shift}]
{Experimental Data};
\node (legend) at ($(group c1r1.south)!0.5!(group c2r1.south)$)
[below, yshift=-2\pgfkeysvalueof{/pgfplots/every axis title shift}]
{\ref{grouplegend}};
\end{tikzpicture}
\end{document}