12

I have adapted a piece of code that I found on the Q&A forum multiple legends in pgfplots as follows in order to include the legend of a drawing directly into the caption:

EDIT 1

\documentclass[a4paper]{book}
\usepackage{lipsum}
\usepackage{pgfplots}
\usepackage[left=3.8cm,right=3.8cm,a4paper]{geometry}
\pgfplotsset{compat=1.3}
\begin{document}
\lipsum[1-2]
\begin{figure}[!ht]
\centering
\begin{tikzpicture}
\begin{axis}[height=6cm,width=8.5cm,grid=major,xlabel=$x$,ylabel=$f(x)$,tick label style={font=\small},label style={font=\small},title style={font=\small},every axis title shift=0pt,max space between ticks=30,major tick length=0cm,minor tick length=0cm,enlargelimits=false,]
\addplot expression[domain=-6:6] {0.4*x};\label{p4}
\addplot{0.5*x};\label{p5}
\addplot{0.6*x};\label{p6}
\end{axis}
\end{tikzpicture}\par
% boxes for caption 1
\newbox{\captionA}%
\savebox{\captionA}{(\small\tikz[baseline]\node at (0,2.5pt){\ref{p4}};)}%
\newbox{\captionB}%
\savebox{\captionB}{(\small\tikz[baseline]\node at (0,2.5pt){\ref{p5}};)}%
\newbox{\captionC}%
\savebox{\captionC}{(\small\tikz[baseline]\node at (0,2.5pt){\ref{p6}};)}%
\caption{This is a plot about curves in color such as $f(x)=0.4 x$\usebox{\captionA},  $f(x)=0.5 x$\usebox{\captionB} and $f(x)=0.6 x$\usebox{\captionC}}
\end{figure}
\lipsum[1-2]
\end{document}

but as may you may notice, the brackets around the colored ref are a bit too far: is it possible to control this?

EDIT 2: final answer

\documentclass{book}
\usepackage{lipsum}
\usepackage{caption}
\usepackage{pgfplots}
\pgfplotsset{compat=1.3}
\tikzset{pointille/.style={dash pattern = on 2pt off 2pt on 6pt off 2pt}}
\tikzset{points/.style={dash pattern = on 1pt off 1pt}}
\tikzset{tirets/.style={dash pattern = on 5pt off 5pt}}

\begin{document}
\lipsum[1]
\begin{figure}[!ht]
\centering
\captionsetup{width=9.5cm}
\pgfplotsset{every axis plot post/.append style={mark=none,line width=1.5pt}}
\begin{tikzpicture}
\begin{axis}[height=7cm,width=9cm,grid=major,xlabel=$x$,ylabel=$f(x)$,
tick label style={font=\footnotesize},label style={font=\small},max space between ticks=45, major tick length=0cm,minor tick length=0cm,enlargelimits=false,]
\addplot[tirets,color=blue]{2x};\label{p4}
\addplot[pointille,color=green]{0.5xx};\label{p5}
\addplot[points,color=red]{-0.125xxx};\label{p6}
\end{axis}
\end{tikzpicture}
\caption[Caption in ToC]{This is a plot about colored curves: $f(x)=2 x$ (\ref{p4}),  $f(x)=0.5 x^2$ (\ref{p5}), and $f(x)=-0.125 x^3$ (\ref{p6})}
\end{figure}
\lipsum[1]
\end{document}

enter image description here

pluton
  • 16,421

2 Answers2

14

The image generated by the \ref command is already neatly sized and positioned, there's no need to wrap it in an additional TikZ picture:

\caption{This is a plot about curves in color such as $f(x)=0.4 x$ (\ref{p4}),  $f(x)=0.5 x$(\ref{p5}) and $f(x)=0.6 x$(\ref{p6})}

yields

Jake
  • 232,450
  • Would you how to achieve the same for the legend in the caption when the plot has been externalized? Redefine the line styles and insert them as TikZ commands? Or can we insert pgfplots commands in the caption? – pluton Feb 01 '21 at 06:44
3

If you add [inner sep=0] to each node declaration, everthing works as is. TikZ adds a little space around each node automatically, which is where the extra space comes from.

Concretely,

\savebox{\captionA}{(\small\tikz[baseline]\node at (0,2.5pt){\ref{p4}};)}%

becomes

\savebox{\captionA}{(\small\tikz[baseline,inner sep=0pt]\node at (0,2.5pt){\ref{p4}};)}%
Justin Bailey
  • 1,921
  • something like this ? \caption{This is a plot about curves in color such as $f(x)=0.4 x$ (\hbox to 18pt{\tikz[baseline,overlay]\node at (9pt,2.5pt){\ref{p4}};}) and $f(x)=0.5 x$ (\hbox to 18pt{\tikz[baseline,overlay]\node at (9pt,2.5pt){\ref{p5}};}), and finally $f(x)=0.6 x$ (\hbox to 18pt{\tikz[baseline,overlay]\node at (9pt,2.5pt){\ref{p6}};})} It is not very automatic ;( – pluton Jun 16 '11 at 17:41
  • If you put the parentheses INSIDE the tikz picture (i.e., \savebox{\captionA}{\small\tikz[baseline]\node at (0,2.5pt){**(**\ref{p4}**)**};} (asterisks added for emphasis), it looks pretty good and you don't have to do all the \hbox stuff. – Justin Bailey Jun 16 '11 at 19:53