Plot data in rows without x coordinate given using strings as x tick labels

Question

I'm trying to make a graph, where the label y is the first column of the row and the x is the other columns (in the example it is from IPT1 to IPT7, but it is much more).

I believe it would be a type of histogram or similar to the graphs of electoral surveys (the candidate's name and percentage appears month by month).

I made the code below, but I'm not getting the expected result. The data is generated from a C ++ code (which processes several files and gives the history of the indexes over time).

\documentclass{standalone}
\usepackage{tikz}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\usepackage{filecontents}

\begin{filecontents}{data.dat}
Team;IPT1;IPT2;IPT3;IPT4;IPT5;IPT6;IPT7
Tiger;1;2;3;4;5;6;7
XPO  ;3;5;7;9;11;13;15
ABC  ;5;8;11;14;17;20;23
\end{filecontents}

\begin{document}
\pgfplotstableread[col sep=semicolon]{data.dat}\datatable
\begin{tikzpicture}
   \begin{axis}[
         yticklabels from table={\datatable}{Team},
         ytick=data,
         xticklabel = {IPT1,IPT2,IPT3,IPT4,IPT5,IPT6,IPT7}, xtick=data,
      ]
      \addplot table[
         x=IPT1,
         y expr=\coordindex,
      ] {\datatable};

      \addplot table[
      x=IPT2,
      y expr=\coordindex,
      ] {\datatable};

      \addplot table[
        x=IPT3,
        y expr=\coordindex,
        ] {\datatable};

        \addplot table[
        x=IPT4,
        y expr=\coordindex,
        ] {\datatable};
   \end{axis}
\end{tikzpicture}
\end{document}

I want something like this:

But I'm getting this:

I try put team names in y label and IPT labels on x axis...

Where am I going wrong? And is it possible to assemble a code that reads several columns after the team name (IPT1, IPT2, ..... IPTn)?

Answer 1

There are a few issues in the approach in the question.

The goal is to plot the data for each row, however pgfplots expects the data to be organized in columns. This can be addressed using \pgfplotstabletranspose, using the first column to create keys to refer to each row (see Plot data row-wise with pgfplots).

Note that the row keys are sensitive to spaces, so XPO ;3;5 is different from XPO;3;5. If you want to use spaces in the team names then you need to use curly brackets in the \addplot commands with the exact number of spaces in it, e.g., y = {XPO }.

The x coordinates are not explicitly given in the data, so they should be inferred using \coordindex (which is the position of the value in the row). In the question this command was used for the y value, however the y value should be read from the data itself, because that is what you want to plot. As the rows have been assigned keys you can use y = Tiger etc. to refer to the row for a particular team. To make the lines start at 1 instead of 0 you can use \coordindex+1.

If you want to use a list of strings as tick marks on the x axis then you need to do two separate things: first give a numerical list with tick positions using xtick={...} and also provide the strings with xticklabels={...}. Note that xticklabels has an s at the end, otherwise each individual label is assigned the full list, resulting in the overlapping labels seen in the question. To make the axis more readable you can make the labels a bit smaller using x tick label style.

Finally the position of the team names. In my opinion it does not make much sense to put these names as tick labels on the y axis, because they describe one of the lines in the graph, and not one of the values on the axis. Moreover, the real values (1 to 23 in the example data) presumably have a meaning, for example a score. Therefore it is probably a good idea to use a legend for the team names and put the real y values as labels on the y axis.

Put together in an MWE:

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

\begin{filecontents}{data.dat}
Team;IPT1;IPT2;IPT3;IPT4;IPT5;IPT6;IPT7
Tiger;1;2;3;4;5;6;7
XPO;3;5;7;9;11;13;15
ABC;5;8;11;14;17;20;23
\end{filecontents}

\begin{document}
\pgfplotstableread[col sep=semicolon]{data.dat}\datatable
\pgfplotstabletranspose[colnames from=Team]\transposeddata{\datatable}
\begin{tikzpicture}
   \begin{axis}[
         ylabel = Score,
         xlabel = Task,
         xmin=0,
         xmax=8,
         xtick={1,...,7},
         xticklabels = {IPT1,IPT2,IPT3,IPT4,IPT5,IPT6,IPT7},
         x tick label style={font=\small},
         legend pos = {north west},
      ]
      \addplot table[
         x expr=\coordindex+1,
         y = Tiger,
      ] {\transposeddata};

      \addplot table[
         x expr=\coordindex+1,
         y = {XPO  },
      ] {\transposeddata};


      \addplot table[
         x expr=\coordindex+1,
         y = {ABC  },
      ] {\transposeddata};
      \addlegendentry{Tiger}
      \addlegendentry{XPO}
      \addlegendentry{ABC}      
   \end{axis}
\end{tikzpicture}
\end{document}

Result: