Redefiniendo el entorno multicolumna

Question

Estoy usando mucho multicolum bajo tabularx. En lugar de eliminar espacios

\multicolumn{2}{@{}l}{...}

Quiero crear un nuevo entorno que elimine los espacios finales tanto del frente como del final. ¿Alguna sugerencia para hacer lo mismo? Gracias.

Saludos,

Editar :

Cuando uso el siguiente fragmento de código,

\begin{tabularx}{\textwidth}{@{}Xc@{}}
\toprule\toprule
Some random text & 1,75,650\\\midrule
\multicolumn{2}{@{}l}{\textbf{Panel A1: AAA}} \\\midrule
Number of observations ... & 1,75,650\\

yo obtengo

Pero si uso (@{} eliminado de multicloumn)

\begin{tabularx}{\textwidth}{@{}Xc@{}}
\toprule\toprule
Some random text & 1,75,650\\\midrule
\multicolumn{2}{l}{\textbf{Panel A1: AAA}} \\\midrule
Number of observations ... & 1,75,650\\

yo obtengo

Como tendría que usar \multicolumn{2}{@{}l} varias veces, estaba buscando crear un nuevo entorno. que se encarga de @{}.

Por si alguien busca MWE:

\documentclass{article}
\usepackage{ltablex}
\usepackage{threeparttable}
\usepackage{booktabs}

\title{Document}
\begin{document}
\maketitle

\begin{tabularx}{\textwidth}{Xc}
\toprule\toprule
Some random text & 1,75,650\\\midrule
\multicolumn{2}{l}{\textbf{Panel A1: AAA}} \\\midrule
Number of observations ... & 1,75,650\\
Delete: ... & (78,420)\\
Delete: ... & (7,104)\\
Final sample & 90,126\\
Delete: & (2,143)\\
Delete: & (8,345)\\
Final sample & 79,638\\\midrule
\multicolumn{2}{l}{\textbf{Panel A2: AAA}} \\\midrule
Number of observations & 79,638\\
Delete: & (39,540)\\
Delete: & (7,979) \\
Final sample & 32,119 \\\midrule
\multicolumn{2}{l}{\textbf{Panel B1: BBB }} \\\midrule
Number of observations  & 1,75,650\\
Delete: & (78,420)\\
Delete: & (47,136)\\
Delete: & (7,178)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Final sample & 42,884\\\midrule
\multicolumn{2}{l}{\textbf{Panel B2: BBB}} \\\midrule
Number of observations  & 1,75,650\\
Delete: & (78,420)\\
Delete: & (47,136)\\
Delete: & (7,178)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Number of observations  & 1,75,650\\
Delete: & (78,420)\\
Delete: & (47,136)\\
Delete: & (7,178)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Final sample & 42,884\\\midrule\bottomrule
\end{tabularx}

\end{document}

Editar: En caso de que alguien pueda estar interesado, así es como lo definí:

\newcommand{\gmc}[2]{\multicolumn{#1}{@{}#2@{}}}

Answer 1

Un ejemplo con tabularrayun nuevo comando de tabla \gmc:

\documentclass[twocolumn]{article}

\usepackage{tabularray}
\UseTblrLibrary{booktabs}

\NewTableCommand{\gmc}{\SetCell[c=2]{l}\SetRow{font=\bfseries}}

\DefTblrTemplate{contfoot-text}{default}{To be continued}
\DefTblrTemplate{conthead-text}{default}{(continued)}

\title{Document}
\author{}

\begin{document}

\maketitle

\begin{longtblr}[
    caption={A table \emph{without} initial and final space before the columns}
    ]{
    colspec={Xc},
    column{1}={leftsep=0pt},
    column{Z}={rightsep=0pt},
    }
\toprule\toprule
Some random text & 1,75,650\\\midrule
\gmc Panel A1: AAA \\\midrule
Number of observations ... & 1,75,650\\
Delete: ... & (78,420)\\
Delete: ... & (7,104)\\
Final sample & 90,126\\
Delete: & (2,143)\\
Delete: & (8,345)\\
Final sample & 79,638\\\midrule
\gmc Panel A2: AAA \\\midrule
Number of observations & 79,638\\
Delete: & (39,540)\\
Delete: & (7,979) \\
Final sample & 32,119 \\\midrule
\gmc Panel B1: BBB \\\midrule
Number of observations  & 1,75,650\\
Delete: & (78,420)\\
Delete: & (47,136)\\
Delete: & (7,178)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Final sample & 42,884\\\midrule
\gmc Panel B2: BBB\\\midrule
Number of observations  & 1,75,650\\
Delete: & (78,420)\\
Delete: & (47,136)\\
Delete: & (7,178)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Number of observations  & 1,75,650\\
Delete: & (78,420)\\
Delete: & (47,136)\\
Delete: & (7,178)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Final sample & 42,884\\\midrule\bottomrule
\end{longtblr}

\begin{longtblr}[
    caption={A table \emph{with} initial and final space before the columns}
    ]{
    colspec={Xc}
    }
\toprule\toprule
Some random text & 1,75,650\\\midrule
\gmc Panel A1: AAA \\\midrule
Number of observations ... & 1,75,650\\
Delete: ... & (78,420)\\
Delete: ... & (7,104)\\
Final sample & 90,126\\
Delete: & (2,143)\\
Delete: & (8,345)\\
Final sample & 79,638\\\midrule
\gmc Panel A2: AAA \\\midrule
Number of observations & 79,638\\
Delete: & (39,540)\\
Delete: & (7,979) \\
Final sample & 32,119 \\\midrule
\gmc Panel B1: BBB \\\midrule
Number of observations  & 1,75,650\\
Delete: & (78,420)\\
Delete: & (47,136)\\
Delete: & (7,178)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Final sample & 42,884\\\midrule
\gmc Panel B2: BBB\\\midrule
Number of observations  & 1,75,650\\
Delete: & (78,420)\\
Delete: & (47,136)\\
Delete: & (7,178)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Number of observations  & 1,75,650\\
Delete: & (78,420)\\
Delete: & (47,136)\\
Delete: & (7,178)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Delete: & (32)\\
Final sample & 42,884\\\midrule\bottomrule
\end{longtblr}
\end{document}

Fuera de tema: tu número 1,75,650 es bastante extraño.