[Tex/LaTex] Numbers centered above clustered bar graph in pgfplots

pgfplots

I want make a bar graph with clusters of two bars together, just like in the below code. However, I want to have one number centered above the two bars, instead of having two numbers above each bar. How can I do this?

MWE (taken from pgfplots manual):

\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}

\pagestyle{empty}

\begin{document}
\begin{tikzpicture}
\begin{axis}[
    x tick label style={
        /pgf/number format/1000 sep=},
    ylabel=Population,
    enlargelimits=0.15,
    legend style={at={(0.5,-0.15)},
        anchor=north,legend columns=-1},
    ybar=5pt,% configures `bar shift'
    bar width=9pt,
    nodes near coords,
    point meta=y *10^-7 % the displayed number
]
\addplot 
    coordinates {(1930,50e6) (1940,33e6)
         (1950,40e6) (1960,50e6) (1970,70e6)};

\addplot 
    coordinates {(1930,38e6) (1940,42e6) 
        (1950,43e6) (1960,45e6) (1970,65e6)};

\legend{Far,Near}
\end{axis}
\end{tikzpicture}
\end{document}

Best Answer

You can also have pgfplots calculate the difference for you:

\documentclass{article}
\usepackage{pgfplots,pgfplotstable}
\pgfplotsset{compat=1.14}

\pgfplotstableread{
x y1 y2
1930 50e6 38e6
1940 33e6 42e6
1950 40e6 43e6
1960 50e6 45e6
1970 70e6 65e6
}\mydata

\begin{document}
\begin{tikzpicture}
\begin{axis}[
    ymin=0,
    x tick label style={
        /pgf/number format/1000 sep=},
    ylabel=Population,
    enlarge x limits=0.15,
    legend style={at={(0.5,-0.15)},
        anchor=north,legend columns=-1},
    ybar=5pt,% configures `bar shift'
    bar width=9pt,
]
\addplot table[x=x,y=y1] {\mydata};
\addplot table[x=x,y=y2] {\mydata};

\addplot [
  only marks,
  point meta=explicit,
  nodes near coords={\pgfmathprintnumber[precision=1,showpos]{\pgfplotspointmeta}\%},
  nodes near coords style={above}
  ]
  table[
    x=x,
    y expr={max(\thisrow{y1},\thisrow{y2})},
    meta expr={(\thisrow{y2}-\thisrow{y1})/\thisrow{y1} * 100}] {\mydata};

\legend{Far,Near}
\end{axis}
\end{tikzpicture}
\end{document}

Related Solutions

[Tex/LaTex] plotting two time series with bounds

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}

[Tex/LaTex] How to apply nodes near coords to a single bar / to a single plot

That's a lot of questions in a single post. This site works best if you ask about a single issue per post, preferably in such a way that other people with similar problems have a chance of finding the question. I would suggest that for each question in your post, you open a new issue where you try to generalise and whittle down the problem in such a way that it is "googleable". For example, your first question could be phrased as "How do I apply nodes near coords to a single bar / to a single plot?".

That said, here are quick answers for your four questions:

You can specify the nodes near coords in the \addplot [...] options instead of in the \begin{axis}[...] options. That way, it will only apply for that plot.
See How can I add a zero line to a plot?
You can change the relevant entry in the table from 25--29 to \bfseries 25--29.
Set enlarge y limits={abs=1}, enlarge x limits=false (or similar).

Best Answer

Related Solutions

[Tex/LaTex] plotting two time series with bounds

[Tex/LaTex] How to apply nodes near coords to a single bar / to a single plot

Related Question