[Tex/LaTex] Misplaced \omit and \multicolumn in \IfEqCase

conditionalsmacrosmulticolumntablesxstring

I have the following code with a command that creates rows for a tabular:

\documentclass[letterpaper,10pt]{article}
\usepackage[utf8]{inputenc}
\usepackage{xstring}

\newcommand*{\condrow}[2]{
\IfEqCase{#1}{
 {l}{#2 & & \\}
 {r}{ & & #2 \\}
 {c}{ & #2 & \\}
 {m}{\multicolumn{3}{c}{#2} \\}
}[\PackageError{condrow}{Undefined option: #1}{}]
}

\begin{document}
\begin{tabular}{|c|c|c|}
 \condrow{l}{left}
 \condrow{r}{right}
 \condrow{c}{center}
 \multicolumn{3}{c}{manual multi} \\ % WORKS
 \condrow{m}{condrow multi} % FAILS
\end{tabular}
\end{document}

While using the \multicolumn directly in the tabular works, using \multicolumn through the command \condrow fails.
My guess is that \IfEqCase in \condrow prepends something to the beginning of the \multicolumn command, triggering the following error:

! Misplaced \omit.
\multispan -&gt;\omit 
                   \@multispan 
l.20  \condrow{m}{condrow multi}
                                 % FAILS

Prepending \\ before \multicolumn in the command makes the error disappear, but inserts an empty row.
The problem Misplaced \omit. \multispan with \newcommand is similar. However, the answers do not solve my case. I have tried using the ifthen package for branching without success.

Any ideas how to fix this?

Best Answer

An expl3 solution:

\documentclass[letterpaper,10pt]{article}
\usepackage{xparse}

\ExplSyntaxOn
\DeclareExpandableDocumentCommand{\condrow}{ m m }
 {
  \str_case:nnF { #1 }
   {
    { l } { #2 &    &    \\ }
    { r } {    &    & #2 \\ }
    { c } {    & #2 &    \\ }
    { m } { \multicolumn{3}{c}{#2} \\ }
   }
   { \PackageError{condrow}{Undefined~option:~#1}{<explanation>} }
 }
\ExplSyntaxOff

\begin{document}
\begin{tabular}{|c|c|c|}
  \condrow{l}{left}
  \condrow{r}{right}
  \condrow{c}{center}
  \condrow{m}{condrow multi}
\end{tabular}
\end{document}

This has the advantage of being more easily extended to accept new options.

enter image description here

Related Solutions

[Tex/LaTex] “! Misplaced \omit” error

You cannot place a \label as the first element in a cell. If you're interested in labelling the table, place the tabular in a table environment, add a \caption and place the \label after it:

enter image description here

\documentclass{article}
\begin{document}
\begin{table}
  \centering
  \begin{tabular}{c|c|c|c|c|}
    \cline{2-5}
    & \multicolumn{2}{|c}{1 Sec Trials} & \multicolumn{2}{|c|}{100 Sec Trials} \\
    \hline
    \multicolumn{1}{|c|}{Target Rate} & Mean & Std. Dev & Mean & Std. Dev \\
    \hline
    \multicolumn{1}{|r|}{1Hz} & 1.07 & 1.08 & 1.22 & 0.11 \\
    \multicolumn{1}{|r|}{5Hz} & 4.71 & 2.09 & 4.51 & 0.21 \\
    \multicolumn{1}{|r|}{10Hz} & 10.3 & 3.28  & 10.1 & 0.32 \\
    \multicolumn{1}{|r|}{100Hz} & 93.6 & 9.91 & 94.6 & 0.97 \\
    \hline
  \end{tabular}
  \caption{Here is a caption}\label{tlc}
\end{table}
\end{document}

Here is a booktabs alternative to your tabular:

enter image description here

\documentclass{article}
\usepackage{booktabs}% http://ctan.org/pkg/booktabs
\begin{document}
\begin{table}
  \centering
  \begin{tabular}{r*{4}{c}}
    \toprule
    & \multicolumn{2}{c}{1 Sec Trials} & \multicolumn{2}{c}{100 Sec Trials} \\
    \cmidrule(lr){2-3} \cmidrule(lr){4-5}
    Target Rate & Mean & Std. Dev & Mean & Std. Dev \\
    \midrule
    1Hz & 1.07 & 1.08 & 1.22 & 0.11 \\
    5Hz & 4.71 & 2.09 & 4.51 & 0.21 \\
    10Hz & 10.3 & 3.28  & 10.1 & 0.32 \\
    100Hz & 93.6 & 9.91 & 94.6 & 0.97 \\
    \bottomrule
  \end{tabular}
  \caption{Here is a caption}\label{tlc}
\end{table}
\end{document}

[Tex/LaTex] Multicolumn misplaced \omit problem

You could place \hline at the end of the first and last line. You could use the column format |c| in the multicolumn. Setting \renewcommand{\arraystretch}{3} or some other more appropriate value can get the horizontal rules not to squeeze the lines too much.

\documentclass{article}
\pagestyle{empty}
\begin{document}
\begin{table}[h]
     \begin{tabular}{|c|c|c|c|c|c|c|c|}\hline
     \multicolumn{8}{|c|}{Dataset A} \\\hline
 L (m)  & T (s) & T$^2$ (s$^2$) & L$^{1/2}$ (m$^{1/2}$) & $\Delta$T$^2$ (s$^2$) & $\Delta$T (s) & Fitted T$^2$ (s$^2$) & Fitted T (s) \\ \hline
    0.2 & 0.626 & 0.392         & 0.447                 & 0.006                 & 0.005         & 0.394                & 0.662 \\ 
    0.3 & 0.889 & 0.790         & 0.548                 & 0.009                 & 0.005         & 0.797                & 0.889 \\ 
    0.4 & 1.105 & 1.221         & 0.632                 & 0.011                 & 0.005         & 1.201                & 1.081 \\ 
    0.5 & 1.261 & 1.590         & 0.707                 & 0.013                 & 0.005         & 1.604                & 1.250 \\ 
    0.6 & 1.420 & 2.016         & 0.775                 & 0.014                 & 0.005         & 2.008                & 1.403 \\ 
    0.7 & 1.555 & 2.418         & 0.837                 & 0.016                 & 0.005         & 2.411                & 1.543 \\ 
    0.8 & 1.679 & 2.819         & 0.894                 & 0.017                 & 0.005         & 2.814                & 1.674 \\ 
    0.9 & 1.798 & 3.233         & 0.949                 & 0.018                 & 0.005         & 3.218                & 1.797 \\ 
    1.0 & 1.901 & 3.614         & 1.000                 & 0.019                 & 0.005         & 3.621                & 1.913 \\ 
    1.1 & 2.000 & 4.000         & 1.049                 & 0.020                 & 0.005         & 4.025                & 2.023 \\\hline
\end{tabular}
\end{table}

\end{document}

enter image description here

Here's an example where the \arraystretch has been set to 1.5:

enter image description here

Best Answer

Related Solutions

[Tex/LaTex] “! Misplaced \omit” error

[Tex/LaTex] Multicolumn misplaced \omit problem

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