[Tex/LaTex] How to use variables (or formatting commands) in a header row of a \pgfplotstable table

pgfplotstabletables

My first reaction to reading the pgfplotstable manual was:

Why would anybody in their right mind use the tabular environment for generating tables?

Advantages of pgfplotstable

No need to specify number of columns
Global formatting settings
Local formatting settings that can override global settings when necessary (etc. longtable needed, changes in cell alignment, etc.)

In my experiments with pgfplotstable, I've run into some bumps:

merging multiple columns
adding formatting commands to text within header rows

Problem

columns/<name>/.style is the issue. Formatting commands and new commands cannot be used as column identifiers (called "names" in pgfplotstable). I need to find a way to keep the text names in the header row (for pdf output), but tell pgfplotstable to use column indexes (e.g. 0,1,2,etc.) for uniquely identifying the columns.
I use a \texttt{} in my command and the file fails to typeset.
I also use \texttt{} inside of a \newcommand to demonstrate both cases.

Example of Issue

Given:

\newcommand\test{\texttt{hello}.bye}
\pgfplotstabletypeset{%
col1 & \test{} & col3\\
here & more & stuff\\
}%

Results in:

columns/col1/.style={}
columns/\texttt{hello}.bye/.style={} % Not a valid column name!
columns/col3/.style={}

Obviously the second column (index 1) does not work as Percusse mentioned in a comment.

This leaves me with the conlusion that the solution might involve automatically stripping the formatting from column names OR forcing pgfplotstable to use indexes (0,1,2, etc.) in place of names. In either case, the columns must become valid keys for pgfplotstable to reference:**

columns/col1/.style={}
columns/hello.bye/.style={}
columns/col3/.style={}

columns/0/.style={}
columns/1/.style={}
columns/2/.style={}

Example that works

Desired result: replace a cell with \test{}.

\documentclass{article}
\usepackage{fontspec}
\usepackage{booktabs}
\usepackage{pgfplotstable}
\pgfplotstableset{% Global config
    every head row/.style={before row=\toprule,after row=\midrule},
    every last row/.style={after row=\bottomrule},
    col sep=&,
    row sep=\\,
    column type=l,
    column type={>{\fontseries{bx}\selectfont\color{orange}}l}, %see sec 2.6 for defining column types
    string type,
    postproc cell content/.append style={ % see sec 3.2
    /pgfplots/table/@cell content/.add={\fontseries{\seriesdefault}\selectfont\color{black}}{}}
}%
\newcommand\test{\texttt{test}.bye}

\begin{document}
\pgfplotstabletypeset{%
col1 & col2 & col3\\ % <-- I want to replace a cell with \test{} in a header row
here & more & stuff\\
for & good & looks\\
}%
\end{document}

Example that does not work

Desired result: replace a cell with \test{}.

\documentclass{article}
\usepackage{fontspec}
\usepackage{booktabs}
\usepackage{pgfplotstable}
\pgfplotstableset{% Global config
    every head row/.style={before row=\toprule,after row=\midrule},
    every last row/.style={after row=\bottomrule},
    col sep=&,
    row sep=\\,
    column type=l,
    column type={>{\fontseries{bx}\selectfont\color{orange}}l}, %see sec 2.6 for defining column types
    string type,
    postproc cell content/.append style={ % see sec 3.2
    /pgfplots/table/@cell content/.add={\fontseries{\seriesdefault}\selectfont\color{black}}{}}
}%
\newcommand\test{\texttt{test}.bye}

\begin{document}
\pgfplotstabletypeset{%
col1 & \test{} & col3\\ % <-- I want to replace a cell with \test{} in a header row
here & more & stuff\\
for & good & looks\\
}%
\end{document}

Huge thanks to Symbol 1 and Guuk for making this possible:

The ability to:

globally format specific rows (see Pgfplotstable one row in bold)
override global formatting with standard latex formatting (important detail: also in header rows by cheating—see Symbol 1's answer)
include commands within header rows (again cheating—see Symbol's answer)

enter image description here

Demonstration

\documentclass{article}
\usepackage{booktabs}
\usepackage{pgfplotstable}
\usepgflibrary{decorations.fractals}

\pgfplotstableset{
    string type,col sep=&,row sep=\\,
    header=false,
    every head row/.style={output empty row},
    every row no 0/.style={before row=\toprule,after row=\midrule},
    every last row/.style={after row=\bottomrule},
    highlightrow/.style={
        postproc cell content/.append code={
           \count0=\pgfplotstablerow
            \advance\count0 by1
            \ifnum\count0=#1
            \pgfkeysalso{@cell content/.add={\bfseries\color{red}}{}}
            \fi
        },
    },
    highlightrow={1}
}%

\begin{document}

\pgfplotstabletypeset{
    \LaTeX & \textit{italic} & \textcolor{orange}{orange} & \reflectbox{reflect} & $e^{i\pi}+1=0$ & \tikz\draw[decoration=Koch snowflake]decorate{decorate{decorate{decorate{(0,0)--(1,0)}}}}; \\
    Lorem & ipsum & dolor & sit & amet & consectetur \\
    adipisicing & elit & sed & do & eiusmod & tempor \\
}

\end{document}

Best Answer

Show me a solution

This is "a" solution that uses row no 0 as the header. (usually the header is row no -1). So PgfplotsTable will no longer put the entries inside \csname. Notice that you need to reset the style for row no 0 if you assign some style for some columns.

\documentclass{article}
\usepackage{booktabs}
\usepackage{pgfplotstable}
\usepgflibrary{decorations.fractals}

\begin{document}

\pgfplotstabletypeset[
    string type,col sep=&,row sep=\\,
    header=false,
    every head row/.style={output empty row},
    every row no 0/.style={before row=\toprule,after row=\midrule},
    every last row/.style={after row=\bottomrule},
]{
    \LaTeX & \textit{italic} & \textcolor{orange}{orange} & \reflectbox{reflect} & $e^{i\pi}+1=0$ & \tikz\draw[decoration=Koch snowflake]decorate{decorate{decorate{decorate{(0,0)--(1,0)}}}}; \\
    Lorem & ipsum & dolor & sit & amet & consectetur \\
    adipisicing & elit & sed & do & eiusmod & tempor \\
}

\end{document}

Combining with cell-processing (update)

There are ≥3 stages of cell-processing. Perhaps typeset cell is the latest one. (It is even too late to be a processing because there is nothing to do with the literal content then.) Anyway, these keys will probably work as usual.

\pgfplotstabletypeset[
    string type,col sep=&,row sep=\\,
    header=false,
    every head row/.style={output empty row},
    every row no 0/.style={before row=\toprule,after row=\midrule},
    every last row/.style={after row=\bottomrule},
    /pgfplots/table/typeset cell/.code={
        \ifnum\pgfplotstablerow=0
            \ifnum\pgfplotstablecol=\pgfplotstablecols
                \pgfkeyssetvalue{/pgfplots/table/@cell content}{\bfseries\color{orange}#1\\}
            \else
                \pgfkeyssetvalue{/pgfplots/table/@cell content}{\bfseries\color{orange}#1&}
            \fi
        \else
            \ifnum\pgfplotstablecol=\pgfplotstablecols
                \pgfkeyssetvalue{/pgfplots/table/@cell content}{#1\\}
            \else
                \pgfkeyssetvalue{/pgfplots/table/@cell content}{#1&}
            \fi
        \fi
    },
]{
    \LaTeX & \textit{italic} & \textcolor{red}{R}\textcolor{green}{G}\textcolor{blue}{B} & \reflectbox{reflect} & $e^{i\pi}+1=0$ & \tikz\draw[decoration=Koch snowflake]decorate{decorate{decorate{decorate{(0,0)--(1,0)}}}}; \\
    Lorem & ipsum & dolor & sit & amet & consectetur \\
    adipisicing & elit & sed & do & eiusmod & tempor \\
}

Show me the official Solution

Same output as before

\pgfplotstabletypeset[
    string type,col sep=&,row sep=\\,
    every head row/.style={before row=\toprule,after row=\midrule},
    every last row/.style={after row=\bottomrule},
    columns/LaTeX/.style         ={column name=\LaTeX},
    columns/italic/.style        ={column name=\textit{italic}},
    columns/orange/.style        ={column name=\textcolor{orange}{orange}},
    columns/reflect/.style       ={column name=\reflectbox{reflect}},
    columns/eipi+1/.style        ={column name={$e^{i\pi}+1=0$}},
    columns/Koch snowflake/.style={column name={\tikz\draw[decoration=Koch snowflake]decorate{decorate{decorate{decorate{(0,0)--(1,0)}}}};}},
]{
    LaTeX & itslic & orange & reflect & eipi+1 & Koch snowflake \\
    Lorem & ipsum & dolor & sit & amet & consectetur \\
    adipisicing & elit & sed & do & eiusmod & tempor \\
}

Show me the reason

Turns out that this is a basic TeX phenomenon which is totally reasonable but no one will ever, logically, think about it. In the following example, I tried to pack \ttfamily into the name of a control sequence.

\documentclass{minimal}
\begin{document}
    \expandafter\let\csname\ttfamily test\endcsname\relax
\end{document}

Then

\ttfamily is expanded;
a \protect is unveiled;
TeX read \protect before \endcsname and complained.

./236210 copy.tex:7: Missing \endcsname inserted.
<to be read again> 
                   \protect 
l.7   \expandafter\let\csname\ttfamily
                                      test\endcsname\relax
?

(\protect is \relax, it cannot be part of csname. Otherwise it is logically contradictive, right?)

Back to pgfplotstable. This package did plenty of magics and inevitably it put the entry inside a csname. Then BOOM: Since \test led to \texttt to \ttfamily and to \protect, TeX complained!

So the next question may be whether I can replace \newcommand by \edef? For instance

\xdef\test{{\ttfamily test}}

The answer is still NO but for different reason. In fact, due to the design of font-switches, there is internally something like

\xdef \font@name {\curr@fontshape}

But since there is another \edef outside, the following line is executed

\xdef \OT1/cmr/m/n/10 {\OT1/cmr/m/n/10 }

So Once you apply \test... BOOM.

The following paraphrase even gives another error.

\xdef\test{\textit{test}}

Conclusion: Never rely on any specific package for, especially, tables.

Related Solutions

[Tex/LaTex] PGFPlotsTable formatting problems

I see that you have suffered a great deal of frustration. And I am the correct person to receive it as I wrote pgfplotstable, so let me try to accept and ease some of the frustration, and try to help you with it.

Since you stated lots of questions, probably originating in your frustration, I would like to address them:

Are styles defined by columns and can be altered cell by cell?

Hm... partially: the vision is to configure a common appearance for an entire column. Cell-by-cell adoptions are almost not supported, except for some relatively crude mechanisms. This is one of the sources of frustration, I guess.
header/row styles does not care about fixed and precision keys, right?

Yes, correct, as row-based "styles allow to configure the final table code after any cell contents have been assigned."

Consequently, row-based styles do not even allow you to configure "use boldface for my cells". They operate on the entire row, no longer on cells.
Is what I ask possible? If so, how do I achieve it?

Yes, see below.
..."And I could not set bold format"

bold face format is something that beats me whenever I work with numerical tables... and that is probably the reason why it beats you as well (namely because I did still did not offer suitable styles).

The boldface styles for math fonts seem to require the following items
- they need to be given inside of the math mode, i.e. inside of $ and $ which makes it difficult to handle within pgfplotstable
- using \bf is relatively simple, but AFAIK it is discouraged
- \mathbf{...} also requires bracing constructs which is also not really simple to add around existing values (or perhaps pgfplotstable is not really helping here).
I should think about better solutions here eventually.
[...] It looks like the function add is called twice on the integer part and then twice on the decimal part of my number (WTH, this explains why my outputs are so difficult to understand). Is it a bug?

I believe it is a bug, yes. I can reproduce lots of problems with the decimal part splitting. In fact, my solution below excludes dec sep align (and also excludes what you wanted to address with it)

Here is what I came up with. Your table has the requirement that it uses column names which should be formatted as numbers on their own (something which needs adoptions as pgfplotstable assumes plain column names).

As mentioned above, I also failed to integrate dec sep align, something that I should look into eventually. Apparently, it fails to split columns correctly somewhere.

\documentclass{standalone}
\usepackage{array}
\usepackage{booktabs}
\usepackage{colortbl}
\usepackage{pgfplotstable}
\begin{document}
\pgfplotstabletypeset[
    col sep=semicolon,
    font=\footnotesize,
    fixed,precision=2,
    %dec sep align,
    fonts by sign={}{\color{red}},
    every first column/.style={
        fixed zerofill, precision=2,
        postproc cell content/.append style={
            @cell content/.add={$\bf}{$}%
        }%
    },
    assign column name/.style={%
        /pgfplots/table/column name={$\bf \pgfmathprintnumber[fixed zerofill,precision=2]{#1}$}%
    },%
    columns/0.xy/.style={%
        assign column name/.code=,
        column name=\textbf{ABC},
    },
    %debug,
]{
0.xy;0.00;0.01;0.02;0.03;0.04;0.05;0.06;0.07;0.08;0.09
0.00;-1.1;-0.5;-0.326;-0.3;-0.2;-0.1;0.0;0.0;0.0;0.1
0.10;0.1;0.1;0.1;0.2;0.2;0.2;0.2;0.2;0.2;0.2
0.20;0.2;0.3;0.3;0.3;0.3;0.3;0.3;0.3;0.3;0.3
0.30;0.3;0.3;0.3;0.3;0.4;0.4;0.4;0.4;0.4;0.4
0.40;0.4;0.4;0.4;0.4;0.4;0.4;0.4;0.4;0.4;0.4
0.50;0.4;0.4;0.5;0.5;0.5;0.5;0.5;0.5;0.5;0.5
0.60;0.5;0.5;0.5;0.5;0.5;0.5;0.5;0.5;0.5;0.5
0.70;0.5;0.6;0.6;0.6;0.6;0.6;0.6;0.6;0.6;0.6
0.80;0.6;0.7;0.7;0.7;0.7;0.7;0.7;0.7;0.8;0.8
0.90;0.8;0.8;0.9;0.9;1.0;1.1;1.2;1.4;1.7;1.9
};
\end{document}

My personal recommendation would be to use fixed zerofill for all columns instead of dec sep align; it results in

Perhaps you are also interested to see your example with row/col rules, feel free to use or to ignore it:

\documentclass{standalone}
\usepackage{array}
\usepackage{booktabs}
\usepackage{colortbl}
\usepackage{pgfplotstable}
\begin{document}
\pgfplotstabletypeset[
    col sep=semicolon,
    font=\footnotesize,
    fixed, precision=2,
    fixed zerofill,
    %dec sep align,
    fonts by sign={}{\color{red}},
    every first column/.style={
        fixed,fixed zerofill, precision=2,
        postproc cell content/.append style={
            %@cell content/.add={$\bf}{$}%
        }%
    },
    assign column name/.style={%
    %   /pgfplots/table/column name={$\pgfmathprintnumber[fixed,fixed zerofill,precision=2]{#1}$}%
    },%
    columns/0.xy/.style={%
        assign column name/.code=,
        column name=ABC,
        column type=c|,
    },
    every head row/.style={
        before row=\toprule,after row=\midrule},
    every last row/.style={
        after row=\bottomrule},
    %debug,
]{
0.xy;0.00;0.01;0.02;0.03;0.04;0.05;0.06;0.07;0.08;0.09
0.00;-1.1;-0.5;-0.326;-0.3;-0.2;-0.1;0.0;0.0;0.0;0.1
0.10;0.1;0.1;0.1;0.2;0.2;0.2;0.2;0.2;0.2;0.2
0.20;0.2;0.3;0.3;0.3;0.3;0.3;0.3;0.3;0.3;0.3
0.30;0.3;0.3;0.3;0.3;0.4;0.4;0.4;0.4;0.4;0.4
0.40;0.4;0.4;0.4;0.4;0.4;0.4;0.4;0.4;0.4;0.4
0.50;0.4;0.4;0.5;0.5;0.5;0.5;0.5;0.5;0.5;0.5
0.60;0.5;0.5;0.5;0.5;0.5;0.5;0.5;0.5;0.5;0.5
0.70;0.5;0.6;0.6;0.6;0.6;0.6;0.6;0.6;0.6;0.6
0.80;0.6;0.7;0.7;0.7;0.7;0.7;0.7;0.7;0.8;0.8
0.90;0.8;0.8;0.9;0.9;1.0;1.1;1.2;1.4;1.7;1.9
};
\end{document}

I think I have showed some effort to solve my problem. I just get no answer to my post even after starting a bounty. Is my request unfeasible?

When I wrote pgfplotstable, I had relatively special requirements in mind for which I tailored it. In addition, I managed to extend the use-cases to get a relatively powerful tool. I fear that you encountered a use-case which has no natural fit into the offered styling/customization rules. So, perhaps we have to state: "it is unfeasible with pgfplotstable unless one has lots of time, expert knowledge, and love for a tool which does not fit right-away".