# Tabularx misconfiguration with equations

I am trying to make a table like this:

I am using tabularx for creating it, here is the code:

\setlength{\tabcolsep}{2pt}
\renewcommand{\arraystretch}{2}
\newcolumntype{C}[1]{>{\hsize=#1\hsize\centering\let\newline\\\arraybackslash}X}
\renewcommand{\tabularxcolumn}[1]{m{#1}}
\newcommand\fch{0.2}
\newcommand\sch{0.35}
\newcommand\tch{0.3}
\newcommand\fich{0.15}
\begin{tabularx}{\hsize}{|C{\fch}|C{\sch}|C{\tch}|C{\fich}|}
\caption{Calculation, description and reference of the extracted acoustical features.}
\label{acoustic_table} \\
\hline
\multicolumn{4}{|c|}{\textbf{Acoustic Indices}} \\ \hline
\textbf{Acoustic Feature}&  \textbf{Calculation}&  \textbf{Description}&  \textbf{Reference}\\ \hline
Acoustic Complexity Index (frequency-time) ($ACIf_t$) &\vbox{$$\sum_{i=1}^{N_t} \sum_{j=1}^{N_{f-1}} \frac{|I_{i,j}-I_{i,j+1}|}{I_{i,j}+I_{i,j+1}}$$}   & Where $I_{i,j}$ is the normalized amplitude of each pulse in the time step i and frequency bin j, $N_t$ is the number of temporal steps and $N_f$ is the number of frequency bins in the spectrogram. $ACIf_t$ measures the information in two successive frequency bins along each time step. & \cite{Farina2016}\\ \hline
$ACIf_t$ evenness ($ACIf_{te}$) & \vbox{$$\frac{1}{\sum_{i=1}^{N_t}{\sum_{j=1}^{N_{f-1}} \frac{|I_{i,j}-I_{i,j+1}|}{I_{i,j}+I_{i,j+1}}}^{2}}$$}  & Levins evenness applied to the $ACIf_t$. $ACIf_{te}$ measures the distribution of intensity along each time step.  & \cite{Farina2016} \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
\multirow{2}{*}{} &  & \multirow{2}{*}{} & \multirow{2}{*}{} \\ \cline{2-2}
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
\multirow{2}{*}{} &  & \multirow{2}{*}{} & \multirow{2}{*}{} \\ \cline{2-2}
&  &  &  \\ \hline
&  &  &  \\ \hline
\multirow{2}{*}{} &  & \multirow{2}{*}{} & \multirow{2}{*}{} \\ \cline{2-2}
&  &  &  \\ \hline
&  &  &  \\ \hline
\multirow{2}{*}{} &  & \multirow{2}{*}{} & \multirow{2}{*}{} \\ \cline{2-2}
&  &  &  \\ \hline
&  &  &  \\ \hline
\multicolumn{4}{|l|}{} \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
&  &  &  \\ \hline
\end{tabularx}


Which gives me:

But I want to use parenthesis for the second equation, as the first image shows. When I add the parenthesis to that part, I get this:

What can I do to solve this?

• Welcome to TeX.SE. While code snippets are useful in explanations, it is always best to compose a fully compilable MWE that illustrates the problem including the \documentclass and the appropriate packages so that those trying to help don't have to recreate it. Also, the solution may be dependent on the packages that you are using. – Peter Grill Oct 28 '18 at 20:02

## 2 Answers

• you not provide complete small document, so your document layout is unknown, consequently is not known if you have enough space for your table
• caption had not to be inside tabularx environment (or do you use ltablex? this is not clear from your question). i comment it.
• using own preamble and adding parenthesis as you wish i can't reproduce your problem:

used code:

\documentclass{article}
\usepackage[margin=20mm]{geometry}
\usepackage{multirow, tabularx}
\usepackage{amsmath}

\begin{document}
\setlength{\tabcolsep}{2pt}
\renewcommand{\arraystretch}{2}
\newcolumntype{C}[1]{>{\hsize=#1\hsize\centering\let\newline\\\arraybackslash}X}
\renewcommand{\tabularxcolumn}[1]{m{#1}}
\newcommand\fch{0.2}
\newcommand\sch{0.35}
\newcommand\tch{0.3}
\newcommand\fich{0.15}
\begin{tabularx}{\hsize}{|C{\fch}|C{\sch}|C{\tch}|C{\fich}|}
%\caption{Calculation, description and reference of the extracted acoustical features.}
%\label{acoustic_table} \\
\hline
\multicolumn{4}{|c|}{\textbf{Acoustic Indices}} \\ \hline
\textbf{Acoustic Feature}
&  \textbf{Calculation}
&  \textbf{Description}
&  \textbf{Reference}\\ \hline
Acoustic Complexity Index (frequency-time) ($ACIf_t$)
&\vbox{$$\sum_{i=1}^{N_t} \sum_{j=1}^{N_{f-1}} \frac{|I_{i,j}-I_{i,j+1}|}{I_{i,j}+I_{i,j+1}}$$}
& Where $I_{i,j}$ is the normalized amplitude of each pulse in the time step i and frequency bin j, $N_t$ is the number of temporal steps and $N_f$ is the number of frequency bins in the spectrogram. $ACIf_t$ measures the information in two successive frequency bins along each time step.
& \cite{Farina2016} \\ \hline
$ACIf_t$ evenness ($ACIf_{te}$)
& \vbox{$$\frac{1} {\displaystyle \sum\limits_{i=1}^{N_t} \left(\sum\limits_{j=1}^{N_{f-1}} \dfrac{|I_{i,j}-I_{i,j+1}|} {I_{i,j}+I_{i,j+1}} \right)^2 }$$}
& Levins evenness applied to the $ACIf_t$. $ACIf_{te}$ measures the distribution of intensity along each time step.
& \cite{Farina2016} \\ \hline
\end{tabularx}
\end{document}


I solved it using gather for the second equation and adding another pair of braces as indicated in Display equations in tabularx . Although the numbering was not well aligned.

I am sorry I didn't make it clearer