[Tex/LaTex] pgfplotstableread + addplot table: scale column for re-use

pgfmathpgfplotspgfplotstable

I get output files from a code and I want to display the output file with pgfplots. I want to create several different plots with the same files. Therefore, I read them in a macro with pgfplotstable.

I know that the first column contains the x-axis values in seconds. For the plots I want to change the x-axis unit to milliseconds for each and every plot. Currently, I am doing this by multiplying the x-axis value by a thousand for every addplot by x expr=\thisrowno{0}*1000. In my opinion this wastes memory and compile time.

Is it possible to scale the first column values already in the pgfplotstableread?

In this thread I found columns/0/.style={preproc/expr={##1*1000}} for pgfplotstabletypeset but I could not find a similar command to permanently modifiy the values inside \chartdata. I also had a look at write to macro for pgfplotstablesetbut could not make it work.

\documentclass{standalone}
\usepackage{filecontents}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usepackage{pgfplotstable}

\begin{document}

\begin{filecontents}{chartdata.txt}
time               value_1            value_2            value_3
s                  some_unit          some_unit          some_unit
0.                 0.                 0.                 0.         
100.E-09            27.541E-06        580.194E-09         19.8912E-06 
200.E-09            55.082E-06          1.18929E-06       40.2063E-06 
350.E-09            96.3935E-06         2.15546E-06       70.5431E-06 
575.E-09           158.361E-06          3.67572E-06      116.044E-06  
87.4788E-06        24.0925E-03       634.302E-06         17.6932E-03 
652.755E-06        179.775E-03          4.74164E-03      131.941E-03  
750.568E-06        206.714E-03         12.7344E-03       152.076E-03  
760.034E-06        209.321E-03         20.4248E-03       154.317E-03  
760.941E-06        209.571E-03         20.4985E-03       154.679E-03  
\end{filecontents}

\pgfplotstableread[
  skip first n=6, % 2+4 for filecontents header
]{chartdata.txt}{\chartdata}

\begin{tikzpicture}

  \begin{axis}[
    cycle list name=color list,
  ]
    \addplot+[
      % currenty no options
    ] table [
      x expr=\thisrowno{0}*1000,
      y expr=\thisrowno{1},
    ]{\chartdata};
    \addlegendentry{Value 1}
    \addplot+[
      % currenty no options
    ] table [
      x expr=\thisrowno{0}*1000,
      y expr=\thisrowno{2},
    ]{\chartdata};
    \addlegendentry{Value 2}
    \addplot+[
      % currenty no options
    ] table [
      x expr=\thisrowno{0}*1000,
      y expr=\thisrowno{3},
    ]{\chartdata};
    \addlegendentry{Value 3}
  \end{axis}
\end{tikzpicture}

\end{document}

Best Answer

You can create a new column

\pgfplotstablecreatecol
  [create col/expr={\thisrowno{0}*1000}]
  {time in ms}% column name
  \chartdata

and use it with x=time in ms in the plots.

\documentclass{standalone}
\usepackage{filecontents}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usepackage{pgfplotstable}

\begin{document}

\begin{filecontents}{chartdata.txt}
time               value_1            value_2            value_3
s                  some_unit          some_unit          some_unit
0.                 0.                 0.                 0.         
100.E-09            27.541E-06        580.194E-09         19.8912E-06 
200.E-09            55.082E-06          1.18929E-06       40.2063E-06 
350.E-09            96.3935E-06         2.15546E-06       70.5431E-06 
575.E-09           158.361E-06          3.67572E-06      116.044E-06  
87.4788E-06        24.0925E-03       634.302E-06         17.6932E-03 
652.755E-06        179.775E-03          4.74164E-03      131.941E-03  
750.568E-06        206.714E-03         12.7344E-03       152.076E-03  
760.034E-06        209.321E-03         20.4248E-03       154.317E-03  
760.941E-06        209.571E-03         20.4985E-03       154.679E-03  
\end{filecontents}

\pgfplotstableread[
  skip first n=6, % 2+4 for filecontents header
]{chartdata.txt}{\chartdata}

\pgfplotstablecreatecol
  [create col/expr={\thisrowno{0}*1000}]
  {time in ms}% column name
  \chartdata

\begin{tikzpicture}
  \begin{axis}[
    cycle list name=color list,
  ]
    \addplot+[
      % currenty no options
    ] table [
      x=time in ms,
      y index=1,
    ]{\chartdata};
    \addlegendentry{Value 1}
    \addplot+[
      % currenty no options
    ] table [
      x=time in ms,
      y index=2,
    ]{\chartdata};
    \addlegendentry{Value 2}
    \addplot+[
      % currenty no options
    ] table [
      x=time in ms,
      y index=3,
    ]{\chartdata};
    \addlegendentry{Value 3}
  \end{axis}
\end{tikzpicture}
\end{document}

Another possibility is modifying the first column

\documentclass{standalone}
\usepackage{filecontents}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usepackage{pgfplotstable}

\begin{document}

\begin{filecontents}{chartdata.txt}
time               value_1            value_2            value_3
s                  some_unit          some_unit          some_unit
0.                 0.                 0.                 0.         
100.E-09            27.541E-06        580.194E-09         19.8912E-06 
200.E-09            55.082E-06          1.18929E-06       40.2063E-06 
350.E-09            96.3935E-06         2.15546E-06       70.5431E-06 
575.E-09           158.361E-06          3.67572E-06      116.044E-06  
87.4788E-06        24.0925E-03       634.302E-06         17.6932E-03 
652.755E-06        179.775E-03          4.74164E-03      131.941E-03  
750.568E-06        206.714E-03         12.7344E-03       152.076E-03  
760.034E-06        209.321E-03         20.4248E-03       154.317E-03  
760.941E-06        209.571E-03         20.4985E-03       154.679E-03  
\end{filecontents}

\pgfplotstableread[
  skip first n=6, % 2+4 for filecontents header
]{chartdata.txt}{\chartdata}


\pgfplotstablemodifyeachcolumnelement{[index]0}\of\chartdata\as\cell{%
  \pgfkeys{/pgf/fpu=true}%
  \pgfmathparse{1000*\cell}%
  \pgfkeys{/pgf/fpu=false}%
  \edef\cell{\pgfmathresult}%
}%

\begin{tikzpicture}
  \begin{axis}[
    cycle list name=color list,
  ]
    \addplot+[
      % currenty no options
    ] table [
      x index=0,
      y index=1,
    ]{\chartdata};
    \addlegendentry{Value 1}
    \addplot+[
      % currenty no options
    ] table [
      x index=0,
      y index=2,
    ]{\chartdata};
    \addlegendentry{Value 2}
    \addplot+[
      % currenty no options
    ] table [
      x index=0,
      y index=3,
    ]{\chartdata};
    \addlegendentry{Value 3}
  \end{axis}
\end{tikzpicture}
\end{document}

A third possibility is scaling only the xtick labels using

scaled x ticks=false,
xticklabel={%
  \pgfmathparse{\tick*1000}%
  $\pgfmathprintnumber[fixed,precision=1]{\pgfmathresult}$%
}

as options for the axis environment.

\documentclass{standalone}
\usepackage{filecontents}
\usepackage{xintexpr}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usepackage{pgfplotstable}

\begin{document}

\begin{filecontents}{chartdata.txt}
time               value_1            value_2            value_3
s                  some_unit          some_unit          some_unit
0.                 0.                 0.                 0.         
100.E-09            27.541E-06        580.194E-09         19.8912E-06 
200.E-09            55.082E-06          1.18929E-06       40.2063E-06 
350.E-09            96.3935E-06         2.15546E-06       70.5431E-06 
575.E-09           158.361E-06          3.67572E-06      116.044E-06  
87.4788E-06        24.0925E-03       634.302E-06         17.6932E-03 
652.755E-06        179.775E-03          4.74164E-03      131.941E-03  
750.568E-06        206.714E-03         12.7344E-03       152.076E-03  
760.034E-06        209.321E-03         20.4248E-03       154.317E-03  
760.941E-06        209.571E-03         20.4985E-03       154.679E-03  
\end{filecontents}

\pgfplotstableread[
  skip first n=6, % 2+4 for filecontents header
]{chartdata.txt}{\chartdata}

\begin{tikzpicture}
  \begin{axis}[
    cycle list name=color list,
    scaled x ticks=false,
    xticklabel={%
      \pgfmathparse{\tick*1000}%
      $\pgfmathprintnumber[fixed,precision=1]{\pgfmathresult}$%
    }
  ]
    \addplot+[
      % currenty no options
    ] table [
      x index=0,
      y index=1,
    ]{\chartdata};
    \addlegendentry{Value 1}
    \addplot+[
      % currenty no options
    ] table [
      x index=0,
      y index=2,
    ]{\chartdata};
    \addlegendentry{Value 2}
    \addplot+[
      % currenty no options
    ] table [
      x index=0,
      y index=3,
    ]{\chartdata};
    \addlegendentry{Value 3}
  \end{axis}
\end{tikzpicture}
\end{document}

Edit by krtek:

For values larger >16383.9998, e.g. for the y-axis use fpu engine:

scaled y ticks=false,
yticklabel={%
  \pgfkeys{/pgf/fpu=true}%
  \pgfmathparse{\tick*1000}%
  \pgfkeys{/pgf/fpu=false}
  $\pgfmathprintnumber[
    fixed,
    precision=1,
  ]{\pgfmathresult}$%
}

Related Solutions

PGFPlots – Multiple Plots in One File

You can use gnuplot in the background by using \addplot gnuplot [raw gnuplot] {<gnuplot commands>};:

\documentclass{article}
\usepackage{pgfplots}
\usepackage{filecontents}

\begin{filecontents*}{data.txt}
1 1
2 4
3 9
4 16
5 25


1 1
2.5 5
6 12
\end{filecontents*}


\begin{document}
\begin{tikzpicture}
\begin{axis}
\addplot gnuplot [raw gnuplot] {plot 'data.txt' index 0};
\addplot gnuplot [raw gnuplot] {plot 'data.txt' index 1};
\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

Edit by krtek:

Related Solutions

PGFPlots – Multiple Plots in One File

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

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