[Tex/LaTex] pgfplots legend nested in matrix

legendpgfplotstikz-matrix

I'm using a \matrix to arrange subplots, each created using pgfplots. When I tried to use \legend to add a legend to individual plots, lualatex tells me

Package pgf Error: You cannot nest pgfmatrix environments, yet.

How can I label my barseries on a subplot? A combined legend for all subplots is also ok, provided that I can prevent series in different subplots from reusing colors (but I'd prefer not to explicitly choose colors).

My current code looks like

\begin{figure}
   \centering 
   \tikzset{external/export=false}
\resizebox{.9 \columnwidth}{!}{
   \begin{tikzpicture}
     \matrix[ampersand replacement=]{
       \begin{axis}[
         y tick label style={/pgf/number format/fixed, /pgf/number format/fixed zerofill},
         ybar,
         ymin=0, ymax=100, ylabel={\%}, table/y index=2
       ]
         \addplot table[header=false,row sep=\\] { 8 5 2.0833 \\ 9 48 20.0000 \\ 10 187 77.9167 \\ };
         \addplot table[header=false,row sep=\\] { 8 6 2.5000 \\ 9 65 27.0833 \\ 10 169 70.4167 \\ };

         \legend{Series A, Series B}
       \end{axis}
       \pgfmatrixnextcell
       \begin{axis}[
         y tick label style={/pgf/number format/fixed, /pgf/number format/fixed zerofill},
         ybar,
         yticklabel pos=right,
         ymin=0, ymax=100, ylabel={\%}, table/y index=2
       ]
          \addplot table[header=false,row sep=\\] { 37 2 0.8333 \\ 38 3 1.2500 \\ 39 5 2.0833 \\ 40 0 0.0000 \\ 41 7 2.9167 \\ 42 5 2.0833 \\ 43 7 2.9167 \\ 44 7 2.9167 \\ 45 7 2.9167 \\ 46 8 3.3333 \\ 47 9 3.7500 \\ 48 16 6.6667 \\ 49 20 8.3333 \\ 50 13 5.4167 \\ 51 15 6.2500 \\ 52 12 5.0000 \\ 53 11 4.5833 \\ 54 12 5.0000 \\ 55 18 7.5000 \\ 56 7 2.9167 \\ 57 14 5.8333 \\ 58 16 6.6667 \\ 59 5 2.0833 \\ 60 10 4.1667 \\ 61 1 0.4167 \\ 62 4 1.6667 \\ 63 3 1.2500 \\ 64 0 0.0000 \\ 65 1 0.4167 \\ 66 0 0.0000 \\ 67 1 0.4167 \\ 68 0 0.0000 \\ 69 0 0.0000 \\ 70 0 0.0000 \\ 71 1 0.4167 \\ };
          \addplot table[header=false,row sep=\\] { 30 2 0.8333 \\ 31 1 0.4167 \\ 32 2 0.8333 \\ 33 4 1.6667 \\ 34 4 1.6667 \\ 35 3 1.2500 \\ 36 4 1.6667 \\ 37 6 2.5000 \\ 38 5 2.0833 \\ 39 7 2.9167 \\ 40 19 7.9167 \\ 41 17 7.0833 \\ 42 15 6.2500 \\ 43 18 7.5000 \\ 44 11 4.5833 \\ 45 17 7.0833 \\ 46 17 7.0833 \\ 47 14 5.8333 \\ 48 10 4.1667 \\ 49 11 4.5833 \\ 50 8 3.3333 \\ 51 11 4.5833 \\ 52 2 0.8333 \\ 53 7 2.9167 \\ 54 11 4.5833 \\ 55 3 1.2500 \\ 56 4 1.6667 \\ 57 1 0.4167 \\ 58 1 0.4167 \\ 59 2 0.8333 \\ 60 2 0.8333 \\ 61 0 0.0000 \\ 62 0 0.0000 \\ 63 0 0.0000 \\ 64 1 0.4167 \\ };
       \end{axis}
         \\
     };
   \end{tikzpicture}
  }
   \caption{Yup, a caption}
   \label{plot:unique_plot_name}
\end{figure}

The datapoints actually are stored in data files autogenerated from MATLAB scripts, and pulled in via \input. So that's why the plot settings are set on the axis. But this seems unrelated to my legend problems.

Hmm, tex.se just suggested How can I add a legend in aligned subplots

Using pgfplotslibrary{groupplots} and some tweaking of settings, I've achieved

enter image description here

I'd like to use bars for the right-hand plot also, but they overlap by default and I'm still trying to configure family of figures, not individually control each one.

Best Answer

I plotted something similar to what you want using pgfplots. You can edit the legend transparency and its location to best fit what your plot you want to look like.

%pdflatex
\documentclass[margin=5mm]{standalone}
\usepackage{tikz,pgfplots,pgfplotstable}

\usetikzlibrary{patterns}

\begin{document}

\begin{tikzpicture}
\begin{axis}
    [
    ybar stacked,
    title=Bar plot,
    samples=50,point meta rel=axis wide,
    point meta=y,
    legend style={at={(0.075,0.75)},anchor=south west},
    ]
    \addplot table[header=false,row sep=\\] { 8 5 2.0833 \\ 9 48 20.0000 \\ 10 187 77.9167 \\ };
    \addplot table[header=false,row sep=\\] { 8 6 2.5000 \\ 9 65 27.0833 \\ 10 169 70.4167 \\ };
    \legend{Group A, Group B}
    \end{axis}
\end{tikzpicture}
~
\begin{tikzpicture}
\begin{axis}
    [
    title=Line Plot,
    samples=50,
    point meta rel=per plot,
    point meta=y,
    legend style={at={(0.075,0.75)},anchor=south west},
    ]
    \addplot table[header=false,row sep=\\] { 37 2 0.8333 \\ 38 3 1.2500 \\ 39 5 2.0833 \\ 40 0 0.0000 \\ 41 7 2.9167 \\ 42 5 2.0833 \\ 43 7 2.9167 \\ 44 7 2.9167 \\ 45 7 2.9167 \\ 46 8 3.3333 \\ 47 9 3.7500 \\ 48 16 6.6667 \\ 49 20 8.3333 \\ 50 13 5.4167 \\ 51 15 6.2500 \\ 52 12 5.0000 \\ 53 11 4.5833 \\ 54 12 5.0000 \\ 55 18 7.5000 \\ 56 7 2.9167 \\ 57 14 5.8333 \\ 58 16 6.6667 \\ 59 5 2.0833 \\ 60 10 4.1667 \\ 61 1 0.4167 \\ 62 4 1.6667 \\ 63 3 1.2500 \\ 64 0 0.0000 \\ 65 1 0.4167 \\ 66 0 0.0000 \\ 67 1 0.4167 \\ 68 0 0.0000 \\ 69 0 0.0000 \\ 70 0 0.0000 \\ 71 1 0.4167 \\ };
    \addplot table[header=false,row sep=\\] { 30 2 0.8333 \\ 31 1 0.4167 \\ 32 2 0.8333 \\ 33 4 1.6667 \\ 34 4 1.6667 \\ 35 3 1.2500 \\ 36 4 1.6667 \\ 37 6 2.5000 \\ 38 5 2.0833 \\ 39 7 2.9167 \\ 40 19 7.9167 \\ 41 17 7.0833 \\ 42 15 6.2500 \\ 43 18 7.5000 \\ 44 11 4.5833 \\ 45 17 7.0833 \\ 46 17 7.0833 \\ 47 14 5.8333 \\ 48 10 4.1667 \\ 49 11 4.5833 \\ 50 8 3.3333 \\ 51 11 4.5833 \\ 52 2 0.8333 \\ 53 7 2.9167 \\ 54 11 4.5833 \\ 55 3 1.2500 \\ 56 4 1.6667 \\ 57 1 0.4167 \\ 58 1 0.4167 \\ 59 2 0.8333 \\ 60 2 0.8333 \\ 61 0 0.0000 \\ 62 0 0.0000 \\ 63 0 0.0000 \\ 64 1 0.4167 \\ };
    \legend{Group C, Group D}
\end{axis}
\end{tikzpicture}

\end{document}

enter image description here

Related Solutions

[Tex/LaTex] pgfplots particular legend

To add a legend, you just have to call \addlegendentry{label text} at least once, or set the entry/entries in some other way (using \legend{<list of label texts>} or the legend entries={<list of label texts>} key). By default, the label texts are associated with the plots in the sequence they were created.

If, in your example, you add the command \addlegendentry{$f(x)$ after your \addplot command (or before, it doesn't technically matter, but it's more semantic to add it after). Then you will get

Note that a line is shown in the legend, even though it doesn't appear in the plot. That's because you created a line plot, and the legend image doesn't take your filling into account. If you use \addplot [area style] ..., the legend will look like

To add more lines to the legend without associated plots, you can call \addlegendimage{empty legend} and then \addlegendentry as usual. To have the label texts left aligned, you can call legend cell align=left.

\addlegendimage{empty legend}\addlegendentry{$\mu=0$}
\addlegendimage{empty legend}\addlegendentry{$\sigma^2=0.2$}

Here's the complete code:

\documentclass{article}
\usepackage{pgfplots}
\begin{document}
\pgfplotsset{width=10cm}
\begin{tikzpicture}
\makeatletter \newcommand{\pgfplotsdrawaxis}{\pgfplots@draw@axis} \makeatother
\pgfplotsset{axis line on top/.style={
 axis on top=false,
 after end axis/.append code={
    \pgfplotsset{axis line style=opaque,
      ticklabel style=opaque,
      tick style=opaque,
      grid=none}
    \pgfplotsdrawaxis}
  }
}
\pgfdeclarehorizontalshading{stefan}{50bp}{
color(0.00000000000000bp)=(violet);
color(8.33333333333333bp)=(blue);
color(16.66666666666670bp)=(cyan);
color(25.00000000000000bp)=(green);
color(33.33333333333330bp)=(yellow);
color(41.66666666666670bp)=(orange);
color(50.00000000000000bp)=(red)
}
\begin{axis}[
grid=major,
xmin=-0.3, xmax=0.3,
ymin=0, ymax=1,
point meta min={-0.3},
point meta max={0.3},
axis line on top,
tick style={thin,black},
xticklabel style={text height=1.5ex},
xticklabels={%
$-0.4$,
$-0.3$,
$-0.2$,
$-0.1$,
$\mu$,
$0.1$,
$0.2$,
$0.3$,
$0.4$},
extra x ticks={-0.4,-0.3,...,0.4},
extra x tick labels={%
$-0.4$,
$-0.3$,
$-0.2$,
$-0.1$,
$\mu$,
$0.1$,
$0.2$,
$0.3$,
$0.4$},
extra x tick style={
    xticklabel pos=right,
    xticklabel style={text depth=0pt}
},
extra y ticks={0,0.2,...,1},
extra y tick style={
    yticklabel pos=right
},
minor tick num=4,
xlabel=\large $x$,
ylabel=\large $f_{\mu,\sigma^2}(x)$,
colorbar horizontal,
colorbar style={
    xticklabels={%
        $-0.4$,
        $-0.3$,
        $-0.2$,
        $-0.1$,
        $\mu$,
        $0.1$,
        $0.2$,
        $0.3$,
        $0.4$
    },
    xticklabel style={text height=1.5ex}
},
no markers,
colormap={new}{color(0cm)=(violet);color(1cm)=(blue);color(2cm)=(cyan);color(3cm)=(green);color(4cm)=(yellow);color(5cm)=(orange);color(6cm)=(red)},
after end axis/.append code={
    \draw ({rel axis cs:0,0}-|{axis cs:0,0}) -- ({rel axis cs:0,1}-|{axis cs:0,0});
},
legend cell align=left]
\addplot[area style] gnuplot[
    shading=stefan,
    draw=none,
    shader=interp,
    id=DoG,
    samples=1000,
    domain=-0.3:0.3,
    y domain=0:1
]{((1/(sqrt(2*pi*0.00570275999999999)))*exp(-(x-0)**2/(2*0.00570275999999999))/6.603550926)}\closedcycle;
\addlegendentry{$f(x)$}
\addlegendimage{empty legend}\addlegendentry{$\mu=0$}
\addlegendimage{empty legend}\addlegendentry{$\sigma^2=0.2$}
\end{axis}
\end{tikzpicture}
\end{document}

PGFPlots – How to Plot Two Time Series with Bounds Using PGFPlots

This happens because PGFPlots only uses one "stack" per axis: You're stacking the second confidence interval on top of the first. The easiest way to fix this is probably to use the approach described in "Is there an easy way of using line thickness as error indicator in a plot?": After plotting the first confidence interval, stack the upper bound on top again, using stack dir=minus. That way, the stack will be reset to zero, and you can draw the second confidence interval in the same fashion as the first:

\documentclass{standalone}
\usepackage{pgfplots, tikz}

\usepackage{pgfplotstable}

\pgfplotstableread{
temps   y_h y_h__inf    y_h__sup    y_f y_f__inf    y_f__sup    

1   0.237340    0.135170    0.339511    0.237653    0.135482    0.339823    
2   0.561320    0.422007    0.700633    0.165871    0.026558    0.305184    
3   0.694760    0.534205    0.855314    0.074856    -0.085698   0.235411    
4   0.728306    0.560179    0.896432    0.003361    -0.164765   0.171487    
5   0.711710    0.544944    0.878477    -0.044582   -0.211349   0.122184    
6   0.671241    0.511191    0.831291    -0.073347   -0.233397   0.086703    
7   0.621177    0.471219    0.771135    -0.088418   -0.238376   0.061540    
8   0.569354    0.431826    0.706882    -0.094382   -0.231910   0.043146    
9   0.519973    0.396571    0.643376    -0.094619   -0.218022   0.028783    
10  0.475121    0.366990    0.583251    -0.091467   -0.199598   0.016664    
}{\table}

\begin{document}
\begin{tikzpicture}

    \begin{axis}
    % y_h confidence interval
    \addplot [stack plots=y, fill=none, draw=none, forget plot]   table [x=temps, y=y_h__inf]   {\table} \closedcycle;
    \addplot [stack plots=y, fill=gray!50, opacity=0.4, draw opacity=0, area legend]   table [x=temps, y expr=\thisrow{y_h__sup}-\thisrow{y_h__inf}]   {\table} \closedcycle;
    % subtract the upper bound so our stack is back at zero
    \addplot [stack plots=y, stack dir=minus, forget plot, draw=none] table [x=temps, y=y_h__sup] {\table};

    % y_f confidence interval
    \addplot [stack plots=y, fill=none, draw=none, forget plot]   table [x=temps, y=y_f__inf]   {\table} \closedcycle;
    \addplot [stack plots=y, fill=gray!50, opacity=0.4, draw opacity=0, area legend]   table [x=temps, y expr=\thisrow{y_f__sup}-\thisrow{y_f__inf}]   {\table} \closedcycle;

    % the line plots (y_h and y_f)    
    \addplot [stack plots=false, very thick,smooth,blue]  table [x=temps, y=y_h]   {\table};
    \addplot [stack plots=false, very thick,smooth,blue]  table [x=temps, y=y_f]   {\table};
    \end{axis}

\end{tikzpicture}
\end{document}

Best Answer

Related Solutions

[Tex/LaTex] pgfplots particular legend

PGFPlots – How to Plot Two Time Series with Bounds Using PGFPlots

Related Question