[Tex/LaTex] Legend in tikzpicture

legendpgfplotstikz-pgf

I am looking for a way to create a legend in a regular tikzpicture. I found this

Using a pgfplots-style legend in a plain-old tikzpicture

but I don't know

how to put the legend at the wanted position and
how to add an entry with just a number instead of a symbol, like '1 number of ...'.

I don't need this. I just want to create easily a box where I have colored lines, colored circles/rectangles.. and colored numbers and the description next to.

Can anyone help me?

Best Answer

Here is a solution based on Using a pgfplots-style legend in a plain-old tikzpicture. There are two examples: in the first one, the descriptions in the legend are centered, while in the second one, the descriptions are left aligned.

To define numbers in the legend, I added a key number in legend:

% definition to insert numbers
\pgfkeys{/pgfplots/number in legend/.style={%
        /pgfplots/legend image code/.code={%
            \node at (0.295,0){#1};
        },%
    },
}

Centered descriptions

The example:

\documentclass[a4paper,11pt]{article}
\usepackage{tikz}
\usetikzlibrary{calc,shadings}

\usepackage{pgfplots}

% Code from Christian Feuersänger
% https://tex.stackexchange.com/questions/54794/using-a-pgfplots-style-legend-in-a-plain-old-tikzpicture#54834

% argument #1: any options
\newenvironment{customlegend}[1][]{%
    \begingroup
    % inits/clears the lists (which might be populated from previous
    % axes):
    \csname pgfplots@init@cleared@structures\endcsname
    \pgfplotsset{#1}%
}{%
    % draws the legend:
    \csname pgfplots@createlegend\endcsname
    \endgroup
}%

% makes \addlegendimage available (typically only available within an
% axis environment):
\def\addlegendimage{\csname pgfplots@addlegendimage\endcsname}

%%--------------------------------

% definition to insert numbers
\pgfkeys{/pgfplots/number in legend/.style={%
        /pgfplots/legend image code/.code={%
            \node at (0.295,-0.0225){#1};
        },%
    },
}

\begin{document}
\begin{tikzpicture}
\draw (0,0)--(10,0);
\draw(0,-0.2)--(0,0.2)node[above,red]{\small{0}};
\draw(10,-0.2)--(10,0.2)node[above,blue]{\small{1}};
%------------------%
\foreach \m[count=\mi] in {0.909090909,...,9.090909090}
\draw(\m,-0.1)--(\m,0.1) node[anchor=north](a\mi){};
\draw[dotted]($(a2)+(0,0.1)$)--($(a2)+(0,0.4)$);
\draw[dotted]($(a3)+(0,0.1)$)--($(a3)+(0,0.4)$);
\draw[stealth-stealth,red,opacity=0.4]($(a3)+(0,0.4)$)--($(a2)+(0,0.4)$)node[anchor=south west,xshift=0.23cm,black,opacity=1]{\small{$R$}};
%------------------%
\foreach \x/\xtext in {0.7/$u_1$,1.2/$u_2$,4.5/$u_3$,5.2/$u_4$,5.6/$u_5$,7.5/$u_6$}
\shade[ball color=blue]  (\x,0 ) circle (0.1cm) node[below=0.1cm]{\small{\xtext}};
%------------------%
% inf user
\shade[ball color=green]  (0,0 ) circle (0.1cm) node[below=0.1cm]{\small{$u_{inf}$}};

\begin{customlegend}[
legend entries={ % <= in the following there are the entries
$R$: infection radius,
$u_i$: users,
$u_{inf}$: initial infected user, 
social space max dimension,
social space min dimension,
example of rectangle
},
legend style={at={(4.5,3.5)},font=\footnotesize}] % <= to define position and font legend
% the following are the "images" and numbers in the legend
    \addlegendimage{stealth-stealth,red,opacity=0.4}
    \addlegendimage{mark=ball,draw=white}
    \addlegendimage{mark=ball,ball color=green,draw=white}
    \addlegendimage{number in legend=1,blue}
    \addlegendimage{number in legend=0,red}
    \addlegendimage{area legend,orange,fill=orange!20}
\end{customlegend}
\end{tikzpicture}

\end{document}

which gives:

enter image description here

Left aligned descriptions

The code is:

\documentclass[a4paper,11pt]{article}
\usepackage{tikz}
\usetikzlibrary{calc,shadings}

\usepackage{pgfplots}

% Code from Christian Feuersänger
% https://tex.stackexchange.com/questions/54794/using-a-pgfplots-style-legend-in-a-plain-old-tikzpicture#54834

% argument #1: any options
\newenvironment{customlegend}[1][]{%
    \begingroup
    % inits/clears the lists (which might be populated from previous
    % axes):
    \csname pgfplots@init@cleared@structures\endcsname
    \pgfplotsset{#1}%
}{%
    % draws the legend:
    \csname pgfplots@createlegend\endcsname
    \endgroup
}%

% makes \addlegendimage available (typically only available within an
% axis environment):
\def\addlegendimage{\csname pgfplots@addlegendimage\endcsname}

%%--------------------------------

% definition to insert numbers
\pgfkeys{/pgfplots/number in legend/.style={%
        /pgfplots/legend image code/.code={%
            \node at (0.125,-0.0225){#1}; % <= changed x value
        },%
    },
}
\pgfplotsset{
every legend to name picture/.style={west}
}

\begin{document}
\begin{tikzpicture}
\draw (0,0)--(10,0);
\draw(0,-0.2)--(0,0.2)node[above,red]{\small{0}};
\draw(10,-0.2)--(10,0.2)node[above,blue]{\small{1}};
%------------------%
\foreach \m[count=\mi] in {0.909090909,...,9.090909090}
\draw(\m,-0.1)--(\m,0.1) node[anchor=north](a\mi){};
\draw[dotted]($(a2)+(0,0.1)$)--($(a2)+(0,0.4)$);
\draw[dotted]($(a3)+(0,0.1)$)--($(a3)+(0,0.4)$);
\draw[stealth-stealth,red,opacity=0.4]($(a3)+(0,0.4)$)--($(a2)+(0,0.4)$)node[anchor=south west,xshift=0.23cm,black,opacity=1]{\small{$R$}};
%------------------%
\foreach \x/\xtext in {0.7/$u_1$,1.2/$u_2$,4.5/$u_3$,5.2/$u_4$,5.6/$u_5$,7.5/$u_6$}
\shade[ball color=blue]  (\x,0 ) circle (0.1cm) node[below=0.1cm]{\small{\xtext}};
%------------------%
% inf user
\shade[ball color=green]  (0,0 ) circle (0.1cm) node[below=0.1cm]{\small{$u_{inf}$}};

\begin{customlegend}[legend cell align=left, %<= to align cells
legend entries={ % <= in the following there are the entries
$R$: infection radius,
$u_i$: users,
$u_{inf}$: initial infected user, 
social space max dimension,
social space min dimension,
example of rectangle
},
legend style={at={(4.5,3.5)},font=\footnotesize}] % <= to define position and font legend
% the following are the "images" and numbers in the legend
    \addlegendimage{stealth-stealth,red,opacity=0.4}
    \addlegendimage{mark=ball,draw=white}
    \addlegendimage{mark=ball,ball color=green,draw=white}
    \addlegendimage{number in legend=1,blue}
    \addlegendimage{number in legend=0,red}
    \addlegendimage{area legend,orange,fill=orange!20}
\end{customlegend}
\end{tikzpicture}

\end{document}

Result:

enter image description here

Related Solutions

[Tex/LaTex] Using node shapes or self made tikzpicture as image in legend

You can set the code that's used to draw the legend image using legend image code/.code={ ...}:

\documentclass[a4paper,11pt]{article}
\usepackage{tikz}
\usetikzlibrary{shapes.geometric}

\usepackage{pgfplots}

% Code from Christian Feuersänger
% http://tex.stackexchange.com/questions/54794/using-a-pgfplots-style-legend-in-a-plain-old-tikzpicture#54834

% argument #1: any options
\newenvironment{customlegend}[1][]{%
    \begingroup
    % inits/clears the lists (which might be populated from previous
    % axes):
    \csname pgfplots@init@cleared@structures\endcsname
    \pgfplotsset{#1}%
}{%
    % draws the legend:
    \csname pgfplots@createlegend\endcsname
    \endgroup
}%

% makes \addlegendimage available (typically only available within an
% axis environment):
\def\addlegendimage{\csname pgfplots@addlegendimage\endcsname}

%%--------------------------------

% definition to insert numbers
\pgfkeys{/pgfplots/number in legend/.style={%
        /pgfplots/legend image code/.code={%
            \node at (0.295,-0.0225){#1};
        },%
    },
}

\begin{document}
\begin{tikzpicture}

% node shaped as cylinder
\node[shape=cylinder](c) at (0,0){};

% cylinder drawn myself
\draw(3,3)--(4,3);
\draw(3,4)--(4,4);
\draw(3,4) arc [x radius=0.1, y radius=0.5, start angle=90, end angle=270];
\draw(4,3.5) ellipse (0.1 and 0.5);

\begin{customlegend}[legend cell align=left,
legend entries={ cylinder},
legend style={at={(6,3)},font=\footnotesize}]
\addlegendimage{legend image code/.code={\node [draw, cylinder, minimum size=1em] {};}}
\end{customlegend}

\end{tikzpicture}


\end{document}

[Tex/LaTex] Two columns in legend in pgfplots

Simply set the key legend columns=2.

Depending on what you need, you might also be interested in transpose legend and/or reverse legend.

EDIT:

in order to customize the legend's appearance, you can use legend style={<option list>} where <option list> can be any option which applies to a PGF \matrix. All these options can be found in the PGF manual. The one which is necessary here is the column sep key. We have to restrict it to the second column (unless we also want to customize the column separation between images and text).

Here is an example:

\documentclass{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.6}

\begin{document}

\begin{tikzpicture}
    \begin{axis}[
        legend columns=2, 
        legend style={
                    % the /tikz/ prefix is necessary here...
                    % otherwise, it might end-up with `/pgfplots/column 2`
                    % which is not what we want. compare pgfmanual.pdf
            /tikz/column 2/.style={
                column sep=5pt,
            },
        },
    ]
        \addplot {x};
        \addlegendentry{$x$}
        \addplot {x+4};
        \addlegendentry{$x$+4}
    \end{axis}
\end{tikzpicture}

\end{document}

enter image description here

Best Answer

Related Solutions

[Tex/LaTex] Using node shapes or self made tikzpicture as image in legend

[Tex/LaTex] Two columns in legend in pgfplots

Related Question