[Tex/LaTex] Problem in modifying contour label style in pgfplots

pgfplots

I am trying to modify the contour label style in a TikZ picture. I would like to have the label values in the format 0.0 instead of being integers. The following code produces a picture in which labels are shown as integers with no decimal point.

\documentclass[crop=true, border=0mm]{standalone}
\usepackage{pgfplots}

\begin{document}

\begin{tikzpicture}
    \begin{axis}[
        axis on top,
        title = {$\omega_\phi\left(x, \sigma\right) = \frac{\Gamma}{\pi{R_c}^2}\exp\left[-\frac{\left(x-x_0\right)^2+\left(\sigma-R_0\right)^2}{{R_c}^2}\right]$},
        xmin=2, xmax=3,
        ymin=2, ymax=3,
        view={0}{90},
        xlabel = {$x$},
        ylabel = {$\sigma$},
        ]
        \addplot3[
            contour gnuplot = {contour label style={nodes={text=black}}},
            samples=10,
            contour/draw color={black},
            ]
            {1/3.1415927/0.25^2*exp(-((x-2.5)^2+(y-2.5)^2)/0.25^2)};
    \end{axis}
\end{tikzpicture}

\end{document}

The following picture is the result of the above code with 2000 samples.

enter image description here

How can I use the following code to adjust the label value format? For some reasons LaTeX complains about unknown key.

contour label style={
    /pgf/number format/fixed,
    /pgf/number format/precision=1,
}

Best Answer

Code

\documentclass[crop=true, border=0mm]{standalone}
\usepackage{pgfplots}
\begin{document}
\begin{tikzpicture}
    \begin{axis}[
        axis on top,
        title = {$\omega_\phi\left(x, \sigma\right) = \frac{\Gamma}{\pi{R_c}^2}\exp\left[-\frac{\left(x-x_0\right)^2+\left(\sigma-R_0\right)^2}{{R_c}^2}\right]$},
        xmin=2, xmax=3,
        ymin=2, ymax=3,
        view={0}{90},
        xlabel = {$x$},
        ylabel = {$\sigma$},
        ]
        \addplot3[
          contour gnuplot={
            contour label style={
              nodes={text=black},
              /pgf/number format/fixed,
              /pgf/number format/fixed zerofill,
              /pgf/number format/precision=1,
            }
          },
          samples=50,
          contour/draw color={black},
        ]
        {1/3.1415927/0.25^2*exp(-((x-2.5)^2+(y-2.5)^2)/0.25^2)};
    \end{axis}
\end{tikzpicture}
\end{document}

Output

enter image description here

Related Solutions

[Tex/LaTex] pgfplots contour example error

You need to ensure that the path is set correctly. One of the most common frustrations with Windows is the tiny text box used for setting up paths. For any executable to be found one needs to set the "path." Different versions of Windows have slightly different ways to navigate to the input screen, so is best to rather click on "control panel" and search.

An easy way to see, if a path was set-up correctly is to fire up a command prompt console and to type path:

enter image description here

As you can see, easy is an understatement, as is all cluttered under anything close to defaults. If you right click at the top left of the console you can set your console to something larger. You can also adjust some colours if you wish. Good inspiration for color schemes can be found at the sublime2 editor.

A good standalone "Gnuplot" comes bundled with Octave and all necessary settings for windows.

[Tex/LaTex] Problem in adjusting contour label color and numbr of samples in pgfplot

The initial value for the /pgfplots/contour/every contour label key—to which you append with the contour label style key—is ^{_{(pgfplots manual, p. 117,and pgfplotsplothandler.code.tex, ll. 1877ff.)}}:

\pgfplotsset{
  contour/every contour label/.style={
    sloped,
    transform shape,
    inner sep=2pt,
    every node/.style={mapped color!50!black,fill=white},
    /pgf/number format/relative={\pgfplotspointmetarangeexponent},
  }
}

Interesting enough, the initial color (mapped color!50!black) as well as the fill color (to overdraw the plot itself) is set inside the every node style. Why is that so?

Taking a look into pgfplotsplothandlers.code.tex, lines 2071ff., we can see that the every contour label is in fact applied to a scope and not a node. Sneaky!

We can also add stuff to the every node style with either every node/.append style or its short-cut nodes. But use text=black because solely black will also activate a black fill color, and draw=black will only draw the shape’s border.

Now the samples option does actually take effect.

Code

\documentclass[tikz]{standalone}
\usepackage{pgfplots}
\begin{document}
\begin{tikzpicture}
    \begin{axis}[
        title = {$\omega_\phi\left(x, \sigma\right) = \frac{\Gamma}{\pi{R_c}^2}\exp\left[-\frac{\left(x-x_0\right)^2+\left(\sigma-R_0\right)^2}{{R_c}^2}\right]$},
        xmin=1.5, xmax=3.5,
        ymin=1.5, ymax=3.5,
        view={0}{90},
    ]
    \addplot3[
        contour gnuplot={contour label style={every node/.append style={text=black}}},
        samples=100,
        contour/draw color={black},
        ]
    {1/3.1415/0.25^2*exp(-((x-2.5)^2+(y-2.5)^2)/0.25^2)};
    \end{axis}
\end{tikzpicture}
\end{document}

Output

enter image description here

Best Answer

Code

Output

Related Solutions

[Tex/LaTex] pgfplots contour example error

[Tex/LaTex] Problem in adjusting contour label color and numbr of samples in pgfplot

Code

Output

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