Warum schlägt `datatool` fehl, wenn es in einer Tikz-Abbildung verwendet wird?

Question

Betrachten Sie das folgende Beispiel

\documentclass[varwidth=true, border=2pt]{standalone}
\usepackage{tikz}
\usepackage{pgfplots}
\usepackage{datatool}

\begin{filecontents*}[overwrite]{test.csv}
Actual,Class 1,Class 2,Class 3
Class 1,1480.0,0.0,125.0
Class 2,112.0,1303.0,180.0
Class 3,174.0,95.0,1331.0    
\end{filecontents*}

\DTLloaddb[keys={Actual,Class 1,Class 2,Class 3}]% <options>
{test}% <db name>
{test.csv}% <filename>

\newcommand{\fetchdata}[2]{\DTLfetch{test}{Actual}{Class #1}{Class #2}}

\pgfplotsset{compat=1.17}
\begin{document}

Hi \fetchdata{1}{1}

\begin{tikzpicture}
    \begin{axis}[
            colormap={bluewhite}{color=(white) rgb255=(90,96,191)},
            xlabel=Predicted,
            xlabel style={yshift=-30pt},
            ylabel=Actual,
            ylabel style={yshift=20pt},
            xticklabels={Class 1, Class 2, Class 3}, % changed
            xtick={0,...,2}, % changed
            xtick style={draw=none},
            yticklabels={Class 1, Class 2, Class 3}, % changed
            ytick={0,...,2}, % changed
            ytick style={draw=none},
            enlargelimits=false,
            colorbar,
            xticklabel style={
              rotate=00
            },
            nodes near coords={\pgfmathprintnumber\pgfplotspointmeta},
            nodes near coords style={
                yshift=-7pt
            },
        ]
        \addplot[
            matrix plot,
            mesh/cols=3, % changed
            point meta=explicit, draw=gray
        ] table [meta=C] {
            x y C
            0 0 0.5
            1 0 0.01809
            2 0 0.02366
            
            0 1 0.05839
            1 1 0.90109
            2 1 0.01290
            
            0 2 0.06525
            1 2 0.08082
            2 2 0.96344
        };
        
        % Add text in a specific position
        \node[anchor=south, yshift={-20pt}] at (axis cs:0,0) {(1531)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:1,0) {(30)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:2,0) {(33)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:0,1) {(102)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:1,1) {(1494)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:2,1) {(18)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:0,2) {(114)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:1,2) {(134)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:2,2) {(1344)};
    \end{axis}
\end{tikzpicture}
\end{document}

Dadurch entsteht

\DTLfetchWenn ich jedoch versuche, es in die Umgebung einzufügen tikzpicture, heißt das:

\documentclass[varwidth=true, border=2pt]{standalone}
\usepackage{tikz}
\usepackage{pgfplots}
\usepackage{datatool}

\begin{filecontents*}[overwrite]{test.csv}
Actual,Class 1,Class 2,Class 3
Class 1,1480.0,0.0,125.0
Class 2,112.0,1303.0,180.0
Class 3,174.0,95.0,1331.0    
\end{filecontents*}

\DTLloaddb[keys={Actual,Class 1,Class 2,Class 3}]% <options>
{test}% <db name>
{test.csv}% <filename>

\newcommand{\fetchdata}[2]{\DTLfetch{test}{Actual}{Class #1}{Class #2}}

\pgfplotsset{compat=1.17}
\begin{document}

\begin{tikzpicture}
    \begin{axis}[
            colormap={bluewhite}{color=(white) rgb255=(90,96,191)},
            xlabel=Predicted,
            xlabel style={yshift=-30pt},
            ylabel=Actual,
            ylabel style={yshift=20pt},
            xticklabels={Class 1, Class 2, Class 3}, % changed
            xtick={0,...,2}, % changed
            xtick style={draw=none},
            yticklabels={Class 1, Class 2, Class 3}, % changed
            ytick={0,...,2}, % changed
            ytick style={draw=none},
            enlargelimits=false,
            colorbar,
            xticklabel style={
              rotate=00
            },
            nodes near coords={\pgfmathprintnumber\pgfplotspointmeta},
            nodes near coords style={
                yshift=-7pt
            },
        ]
        \addplot[
            matrix plot,
            mesh/cols=3, % changed
            point meta=explicit, draw=gray
        ] table [meta=C] {
            x y C
            0 0 0.5
            1 0 0.\fetchdata{1}{1}
            2 0 0.02366
            
            0 1 0.05839
            1 1 0.90109
            2 1 0.01290
            
            0 2 0.06525
            1 2 0.08082
            2 2 0.96344
        };
        
        % Add text in a specific position
        \node[anchor=south, yshift={-20pt}] at (axis cs:0,0) {(1531)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:1,0) {(30)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:2,0) {(33)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:0,1) {(102)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:1,1) {(1494)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:2,1) {(18)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:0,2) {(114)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:1,2) {(134)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:2,2) {(1344)};
    \end{axis}
\end{tikzpicture}
\end{document}

Ich bekomme

Undefined control sequence.
\edtlgetrowforvalue ...def \@dtl@dogetrowforvalueLaTeX
Undefined control sequence.
\edtlgetrowforvalue ...#3}}\@dtl@dogetrowforvalueLaTeX
Undefined control sequence.
\dtlgetentryfromrow ...3->\edef \@dtl@do@getentryLaTeX
Undefined control sequence.
\dtlgetentryfromrow ...\the #3}}\@dtl@do@getentryLaTeX
Undefined control sequence.
\DTLfetch ...olumnindex {#1}{#4}}\dtlcurrentvalueLaTeX
Missing \endcsname inserted.
<to be read again>LaTeX
Missing \endcsname inserted.
<to be read again>LaTeX
Missing control sequence inserted.
<inserted text>LaTeX
Undefined control sequence.
\dtlgetrowindex ...@ {#4}\edef \dtl@dogetrowindexLaTeX
Undefined control sequence.
\dtlgetrowindex ...he \toks@ }}\dtl@dogetrowindexLaTeX
Undefined control sequence.
\dtlgetrowforvalue ...lse \dtlrownum =\dtl@rowidxLaTeX
Undefined control sequence.
\dtlgetrowforvalue ...idx \relax \edef \dtldbnameLaTeX
Missing \endcsname inserted.
<to be read again>LaTeX
Undefined control sequence.
\dtlgetrowforvalue ...csname \edef \@dtl@dogetrowLaTeX
Undefined control sequence.
\dtlgetrowforvalue ... {\the \toks@ }{\dtl@rowidxLaTeX
Undefined control sequence.
\dtlgetrowforvalue ...dtl@rowidx }}\@dtl@dogetrowLaTeX
Extra }, or forgotten \endgroup.
\pgfmathresult ...romrow {\dtlcurrentvalue }{2}{}}LaTeX
Undefined control sequence.
\dtlgetrowindex ...he \toks@ }}\dtl@dogetrowindexLaTeX
Undefined control sequence.
\dtlgetrowforvalue ...lse \dtlrownum =\dtl@rowidxLaTeX
Missing number, treated as zero.
<to be read again>LaTeX
Undefined control sequence.
\dtlgetrowforvalue ...m =\dtl@rowidx \relax \edefLaTeX
Undefined control sequence.
\dtlgetrowforvalue ...idx \relax \edef \dtldbnameLaTeX
Undefined control sequence.
\dtlgetrowforvalue ...me dtldb@#1\endcsname \edefLaTeX
Undefined control sequence.
\dtlgetrowforvalue ...csname \edef \@dtl@dogetrowLaTeX
Missing \endcsname inserted.
<to be read again>LaTeX
Missing { inserted.
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Undefined control sequence.
\dtlgetrowforvalue ...dtl@rowidx }}\@dtl@dogetrowLaTeX
Missing \endcsname inserted.
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Missing \endcsname inserted.
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Missing \endcsname inserted.
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\GenericError  ...LaTeX
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\GenericError  ...LaTeX
Missing { inserted.
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Missing \endcsname inserted.
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Missing \endcsname inserted.
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Missing \endcsname inserted.
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Extra \fi.
\CheckEncodingSubset ...:\f@family \endcsname \fiLaTeX
Missing \endcsname inserted.
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Extra \else.
\CheckEncodingSubset ...dafter \@firstoftwo \elseLaTeX
Extra \fi.
<recently read> \fiLaTeX
Argument of \tc@subst has an extra }.
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Paragraph ended before \tc@subst was complete.
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Extra \fi.
\GenericError ...rstchoice@ \else 6\fi \endcsnameLaTeX
Extra \fi.
\?-cmd ...ndcsname {\TextSymbolUnavailable #1}\fiLaTeX
Missing \endcsname inserted.
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Paragraph ended before \tc@subst was complete.
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Extra \fi.
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Missing \endcsname inserted.
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Argument of \tc@subst has an extra }.
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Paragraph ended before \tc@subst was complete.
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Extra \fi.
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 ==> Fatal error occurred, no output PDF file produced!
Transcript written on main.log.
Latexmk: Getting log file 'main.log'
Latexmk: Examining 'main.fls'
Latexmk: Examining 'main.log'
Latexmk: Summary of warnings from last run of *latex:LaTeX

Das ergibt keinen Sinn ... Warum \DTLfetchfunktioniert es im Tikz-Bild nicht wie erwartet?

Answer 1

Mit ist es nicht ganz so einfach, \DTLfetchda dieses Makro nicht erweiterbar ist. Sie können jedoch den Ansatz von verwendendiese nette Antwortum die Ausgabe \DTLfetchnach der Erweiterung in einem anderen Makro zu speichern.

Außerdem möchten Sie vermutlich nicht, dass Ihre Eingabe 0.1480.0, sondern nur 0.1480, ist. Sie könnten also ein Makro erstellen, das Ihnen erlaubt, den zurückgegebenen Wert mit einem Faktor zu multiplizieren. Zum Beispiel so:

\documentclass[varwidth=true, border=2pt]{standalone}
\usepackage{pgfplots}
\usepackage{datatool}

\begin{filecontents*}[overwrite]{test.csv}
Actual,Class 1,Class 2,Class 3
Class 1,1480.0,0.0,125.0
Class 2,112.0,1303.0,180.0
Class 3,174.0,95.0,1331.0    
\end{filecontents*}

\DTLloaddb[keys={Actual,Class 1,Class 2,Class 3}]% <options>
{test}% <db name>
{test.csv}% <filename>

\newcommand{\fetchdata}[4][1]{%
    \DTLfetch{test}{Actual}{Class #3}{Class #4}%
    \edtlgetrowforvalue{test}{\dtlcolumnindex{test}{Actual}}{Class #3}%
    \dtlgetentryfromcurrentrow{\dtlcurrentvalue}{\dtlcolumnindex{test}{Class #4}}%
    \pgfmathsetmacro{#2}{#1*\dtlcurrentvalue}%
}

\pgfplotsset{compat=1.17}
\begin{document}

\begin{tikzpicture}
    \begin{axis}[
            colormap={bluewhite}{color=(white) rgb255=(90,96,191)},
            xlabel=Predicted,
            xlabel style={yshift=-30pt},
            ylabel=Actual,
            ylabel style={yshift=20pt},
            xticklabels={Class 1, Class 2, Class 3}, % changed
            xtick={0,...,2}, % changed
            xtick style={draw=none},
            yticklabels={Class 1, Class 2, Class 3}, % changed
            ytick={0,...,2}, % changed
            ytick style={draw=none},
            enlargelimits=false,
            colorbar,
            xticklabel style={
              rotate=00
            },
            nodes near coords={\pgfmathprintnumber\pgfplotspointmeta},
            nodes near coords style={
                yshift=-7pt
            },
        ]
        \fetchdata[0.001]{\myResult}{1}{1}
        \addplot[
            matrix plot,
            mesh/cols=3, % changed
            point meta=explicit, draw=gray
        ] table [meta=C] {
            x y C
            0 0 0.5
            1 0 \myResult
            2 0 0.02366
            
            0 1 0.05839
            1 1 0.90109
            2 1 0.01290
            
            0 2 0.06525
            1 2 0.08082
            2 2 0.96344
        };
        
        % Add text in a specific position
        \node[anchor=south, yshift={-20pt}] at (axis cs:0,0) {(1531)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:1,0) {(30)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:2,0) {(33)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:0,1) {(102)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:1,1) {(1494)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:2,1) {(18)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:0,2) {(114)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:1,2) {(134)};
        \node[anchor=south, yshift={-20pt}] at (axis cs:2,2) {(1344)};
    \end{axis}
\end{tikzpicture}
\end{document}