[Tex/LaTex] How to scale the colorbar to data in pgfplots

graphicspgfplotstikz-pgf

Good morning,

I have some .txt files that contain 3 columns of data: the first one corresponds to the x-axis value of each point, the second one corresponds to the y-axis value of each point, and the third one corresponds to the value that i want in the color bar (meta index).

When I plot the whole thing, the colorbar does not scale with the data in the third column of my txt files.

Here is my code:

\documentclass[varwidth]{standalone}
% *** PACKAGES ***
\usepackage{standalone} % Pour les stand-alone
\usepackage[usenames,dvipsnames]{xcolor} % 68 dvips colors à déclarer avant tikz
\usepackage{tikz} % Pour les figure Tikz
\usepackage{pgfplots} % Pour tracer les courbes à partir de fichiers de données
\usepackage{pgfplotstable} % Pour pouvoir lire les tableaux des fichiers .txt
% *** PACKAGES END ***
\pgfplotsset{compat=1.12} % pour définir la version de pgfplots
\pgfplotsset{
/pgfplots/colormap={hsv2}{rgb255(0cm)=(0,0,0) rgb255(0.10cm)=(128,0,128) rgb255(0.5cm)=(0,0,230)
rgb255(1.cm)=(0,255,255) rgb255(2.5cm)=(0,255,0) rgb255(3.5cm)=(255,255,0) rgb255(6cm)=(255,0,0)}
} % Pour définir les couleurs de la colomap
\begin{document}
\tikzset{mark options={mark size=1.5, line width=0.01pt}}
\begin{tikzpicture}
\begin{axis}[
            clip mode=individual, % Pour plot dans l'ordre
            enlargelimits=false,
    colorbar,
    colorbar style={ylabel=$C_{ligne,si}$},%,ytick={0,0.2,...,1}},
    width=0.7\textwidth,
            height=0.6\textwidth,
    grid=major,
    minor x tick num=1,
            xlabel={Real($\lambda (A)$)},
    minor y tick num=1,
            ylabel={Imag($\lambda (A)$)},
    tick label style={font=\footnotesize},
]
\foreach \m in {1,2,...,100}
{\edef\temp{\noexpand\addplot+[mark=*,only marks,scatter,scatter src=explicit] table[x index=0,y index=1,meta index=2] {./DATA_01/Valeurs_Propres_\m.txt};}\temp}
\end{axis}
\end{tikzpicture}
\end{document}

and here is the end result that I get:

The color bar starts at 10^-6 and goes up to 10^-3; Now I would like the colorbar to scale logarithmically (instead of linearly) so that the "space" between 10^-6 and 10^-5 is the same than between 10^-5 and 10^-4 and between 10^-4 and 10^-3.

I am joining a .zip with my folder containing my .tex files and the .txt files if someone is willing to go this far to help me. You can download it here.

Thank you very much for your help!

Best Answer

In your answer you just show the colorbar in log values, but didn't "transform" the meta data. To do so use meta expr={log10(\thisrowno{2})}. But then the \foreach loop does result in an error, because the meta expr doens't get expanded. To overcome this issue replace the loop with \pgfplotsinvokeforeach.

So that others can reproduce that it works, I have shortened the data files to two files, which together show values including min and max values from the original data files. In the following picture you see the result including all data points.

\begin{filecontents}{DATA_01/Valeurs_Propres_Shortened_1.txt}
    9.92E+00    5.50E+02    6.43E-05
    4.05E+01    5.99E+02    4.98E-05
    7.45E+01    6.52E+02    3.84E-05
    1.12E+02    7.12E+02    2.94E-05
    1.54E+02    7.77E+02    2.23E-05
    2.01E+02    8.51E+02    1.68E-05
    2.53E+02    9.35E+02    1.26E-05
    3.13E+02    1.03E+03    9.29E-06
    3.81E+02    1.14E+03    6.77E-06
    4.60E+02    1.27E+03    4.85E-06
    5.53E+02    1.42E+03    3.41E-06
    6.64E+02    1.61E+03    2.34E-06
    8.00E+02    1.84E+03    1.56E-06
    9.70E+02    2.12E+03    1.00E-06
\end{filecontents}
\begin{filecontents}{DATA_01/Valeurs_Propres_Shortened_2.txt}
    -1.61E+02   2.77E+02    1.00E-03
    -1.57E+02   2.81E+02    8.47E-04
    -1.52E+02   2.88E+02    6.79E-04
    -1.45E+02   2.98E+02    5.42E-04
    -1.37E+02   3.10E+02    4.33E-04
    -1.26E+02   3.25E+02    3.44E-04
    -1.14E+02   3.45E+02    2.73E-04
    -9.96E+01   3.69E+02    2.17E-04
    -8.30E+01   3.97E+02    1.71E-04
    -6.39E+01   4.29E+02    1.35E-04
    -4.22E+01   4.66E+02    1.06E-04
    -1.76E+01   5.06E+02    8.26E-05
\end{filecontents}
\documentclass[varwidth]{standalone}
\usepackage[usenames,dvipsnames]{xcolor}
\usepackage{tikz}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
    \pgfplotsset{
        compat=1.12,
        colormap={hsv2}{
            rgb255(0cm)=(0,0,0)
            rgb255(0.10cm)=(128,0,128)
            rgb255(0.5cm)=(0,0,230)
            rgb255(1.cm)=(0,255,255)
            rgb255(2.5cm)=(0,255,0)
            rgb255(3.5cm)=(255,255,0)
            rgb255(6cm)=(255,0,0)
        },
    }
\begin{document}
    \tikzset{
        mark options={
            mark size=1.5,
            line width=0.01pt,
        },
    }
    \begin{tikzpicture}
        \begin{axis}[
            colorbar,
            colorbar style={
                ylabel=$C_{ligne,si}$,
                yticklabel={$10^{\pgfmathprintnumber{\tick}}$},
            },
            width=0.7\textwidth,
            height=0.6\textwidth,
            grid=major,
            xlabel={Real($\lambda (A)$)},
            ylabel={Imag($\lambda (A)$)},
            tick label style={
                font=\footnotesize,
            },
            % -----
            % added so that the boundaries are very similar
            % to the plot in the question
            xmin=-2600,
            xmax=1000,
            ymin=-2150,
            ymax=2150,
        ]
            \pgfplotsinvokeforeach {1,2} {
                \addplot+ [
                    mark=*,
                    only marks,
                    scatter,
                    scatter src=explicit,
                ] table [
                    x index=0,
                    y index=1,
                    % calculate the log of the data
                    meta expr={log10(\thisrowno{2})},
                ] {DATA_01/Valeurs_Propres_Shortened_#1.txt};
            }
        \end{axis}
    \end{tikzpicture}
\end{document}

Please note, that there are a lot of values three times in the data files. Hopefully this is right and not a copy/paste failure or the like.

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[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    
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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)    
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    \end{axis}

\end{tikzpicture}
\end{document}

[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}

Best Answer

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[Tex/LaTex] plotting two time series with bounds

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

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