[Tex/LaTex] pgfplots won’t produce error bars

pgfplots

The following error is thrown when I try to compile the MWE below:

Package pgfkeys Error: I do not know the key '/tikz/error' and I am going to ignore it.
Perhaps you misspelled it.

I'm running MacTeX 2012 with a fully up-to-date distro.

MWE:

\documentclass[11pt]{standalone}

\usepackage{pgfplots}
\pgfplotsset{compat=1.7}

\begin{document}

\begin{tikzpicture}
  \begin{axis}[
    xmin = 0,
    xmax = 30,
    ymin = 0,
    ymax = 0.45
  ]
    \addplot[
      color = black,
      only marks,
      error bars/.cd,
        y dir = both,
        y explicit,
    ] table[
      y = set1,
      error = stdev% comment out for MWE
    ] {
      mcg set1   set2   set3   stdev
      0   0.0000 0.0000 0.0000 0.0000
      5   0.1031 0.0922 0.0819 0.01
      10  0.1935 0.2137 0.2132 0.01
      15  0.2875 0.2926 0.2888 0.003
      20  0.3373 0.3394 0.3462 0.005
      30  0.4396 0.4328 0.4362 0.003
    };

    \addplot[
      color = red,
      domain = 0:30
    ] {-0.0003*x^2 + 0.0224*x - 0.001};
  \end{axis}
\end{tikzpicture}

\end{document}

Best Answer

You are looking for one of the following keys:

y error that expects a column name (here: stdev),
y error index that expects a column index, or
y error expr that expects an expression.

I also added mark options={mark size=.75} to get a better visual output. The default size looks to big for these errors.

Code

\documentclass[11pt]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.7}
\begin{document}
\begin{tikzpicture}
  \begin{axis}[
    xmin = 0,
    xmax = 30,
    ymin = 0,
    ymax = 0.45
  ]
    \addplot[
      color = black,
      only marks,
      mark options={mark size=.75},
      error bars/.cd,
        y dir = both,
        y explicit,
    ] table[
      y = set1,
      y error = stdev
    ] {
      mcg set1   set2   set3   stdev
      0   0.0000 0.0000 0.0000 0.0000
      5   0.1031 0.0922 0.0819 0.01
      10  0.1935 0.2137 0.2132 0.01
      15  0.2875 0.2926 0.2888 0.003
      20  0.3373 0.3394 0.3462 0.005
      30  0.4396 0.4328 0.4362 0.003
    };

    \addplot[
      color = red,
      domain = 0:30
    ] {-0.0003*x^2 + 0.0224*x - 0.001};
  \end{axis}
\end{tikzpicture}
\end{document}

Output

enter image description here

Related Solutions

[Tex/LaTex] Enlarge error bars in Pgfplots

The error marks are influenced by the key /error bars/error mark options. Using this key resets the initial option, which is rotate=90, so you have to include that as well:

\documentclass{article}

\usepackage{pgfplots}

\begin{document}
\begin{tikzpicture}
\begin{axis}
\addplot+[only marks,
  error bars/.cd,
    y dir=both,
    y explicit,
    error bar style={line width=2pt},
    error mark options={
      rotate=90,
      red,
      mark size=8pt,
      line width=2pt
    }
]
coordinates {
(0,1) +- (0,0.35665)
(1,1.5) +- (0,-0.35048)
(2,0) +- (0,0.150255)
};
\end{axis}
\end{tikzpicture}
\end{document}

custom error bars

[Tex/LaTex] How to hide empty (value 0) ybars with pgfplots

You can use

 y filter/.expression={y==0 ? nan : y}

in the options of \addplot.

\documentclass{article}

% ---------------------------------- tikz
\usepackage{pgfplots}          % to print charts
\pgfplotsset{compat=1.12}

\begin{document}

\begin{figure}
  \centering
  \begin{tikzpicture}
    \begin{axis} [
      % general
      ybar,
      scale only axis,
      height=0.5\textwidth,
      width=1.2\textwidth,
      ylabel={\# Dots},
      nodes near coords,
      xlabel={Variation},
      xticklabel style={
        rotate=90,
        anchor=east,
      },
      %enlarge x limits={abs value={3}},
      ]
      \addplot+[y filter/.expression={y==0 ? nan : y}] table [
        x=grade,
        y=value,
      ] {
grade   value
-11 0
-10 0
-9  0
-8  0
-7  0
-6  0
-5  3
-4  1
-3  2
-2  15
-1  11
0   179
1   8
2   1
3   0
4   1
5   2
6   0
7   0
8   0
9   0
10  0
11  0
      };
    \end{axis}
  \end{tikzpicture}
\end{figure}
\end{document}