Longtable With Multirow and Multicolumn

Question

First of all, thank you for trying to help! This is the problem that I have:

I am trying to create a table that will list a bunch of commands and their description. For that, I need to be able to use multicolumn and multirow features. Also, toprule, midrule, and bottomnrule.

The problem is that the table is longer than one page so I need it to continue on the next page. I found about the longtable package but I cannot seem to be able to figure how to incorporate all of the features I need and still make it work.

I will attach my code for the regular table. Can someone please help me convert it to longtable and keep the formatting the same? I would really appreciate it if someone can help me and also explain how it works because I want to learn it for future use. Big thank you!!!

---

My Code

\documentclass[10pt,english, openany, twoside]{book}

\usepackage[table]{xcolor}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Loading packages that alter the style
\usepackage[]{graphicx}
\usepackage[]{color}
\usepackage{alltt}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\setcounter{secnumdepth}{3}
\setcounter{tocdepth}{3}
\setlength{\parskip}{\smallskipamount}
\setlength{\parindent}{0pt}

% Set page margins
\usepackage[top=1in, bottom=1in, left=1in, right=1in]{geometry}

% Package used for placeholder text
\usepackage{lipsum}

% Prevents LaTeX from filling out a page to the bottom
\raggedbottom

% Adding both languages
\usepackage[english]{babel}

% All page numbers positioned at the bottom of the page
\usepackage{fancyhdr}

\pagestyle{fancy}

\renewcommand{\headrulewidth}{0.0pt}

\fancyhead[LE,RO]{}
\fancyhead[RE,LO]{}
\fancyhead[CE,CO]{}
\fancyfoot[CE,CO]{\thepage}


% Adds table captions above the table per default
\usepackage{float}
%\floatstyle{plaintop}
%\restylefloat{table}

% Adds space between caption and table
\usepackage{caption}
\captionsetup[table]{position=bottom}

% Adds hyperlinks to references and ToC
\usepackage{hyperref}
\hypersetup{hidelinks,linkcolor = black} % Changes the link color to black and hides the hideous red border that usually is created


%Document Styling% <---------%
%%%%%%%%%%%%%%%%%%

\usepackage{float}
\usepackage{array}
\usepackage{hhline} 
\usepackage{arydshln}
\usepackage{caption}
\usepackage{subcaption}
\usepackage{framed}
\usepackage{mdframed} % This frames the sections. However, a command \begin{mdframed}[options] is needed
\usepackage{multicol} % To change column separation use: \setlength{\columnsep}{-3in}
\usepackage{enumitem} % This package removes the indent on the enumeated list. Allows for the command [Leftmargin=*]

%%%%%%%%%%%%%%%%%%


%Graphics% <---------%
%%%%%%%%%%

\usepackage{graphicx}
\usepackage{tikz}
\usetikzlibrary{calc}
\usepackage{xcolor}

%%%%%%%%%%


%Font% <---------%
%%%%%%

\usepackage[T1]{fontenc}
\usepackage{textcomp} % 
\usepackage{hyperref} 
\usepackage{url}
\urlstyle{same}

%%%%%%


%Mathematics% <---------%
%%%%%%%%%%%%%

\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsthm} 
\usepackage{physics}
\usepackage{siunitx} 

%For Table%
%%%%%%%%%%%

\usepackage{booktabs}

\sisetup{
    round-mode          = places, % Rounds numbers
    round-precision     = 2, % to 2 places
}
\usepackage{colortbl}
\usepackage{xfrac}

\definecolor{Gray}{gray}{0.85}

%dashed line
\usepackage{arydshln}
\setlength\dashlinedash{0.2pt}
\setlength\dashlinegap{1.5pt}
\setlength\arrayrulewidth{0.3pt}

\definecolor{codegray}{gray}{0.9}

\usepackage{longtable}

\usepackage{booktabs}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Starts the document
\begin{document}
    
    
     \begin{table}[h!]
        \centering
        \begin{tabular}{llll}
            \toprule
            \multicolumn{4}{c}{\textbf{Serial Command List}} \\
            \toprule
            \textbf{Name} & \textbf{Command} & \textbf{Reply} & \textbf{Description} \\
            \midrule
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            %
            \bottomrule
        \end{tabular} 
        \caption{Serial Command List}
        \label{tab:command-list} 
     \end{table}
    

\end{document}

---

Output

Answer 1

The following whould serve as a point to start from. I moved the caption to the beginning of the table. If you want the column headers to repeat on the second and following pages of your table, take a look at the difference od \enfirstthead and \endhead.

As already mentioned in the comments, the load order of packages matters, when you want to combine longtable, hyperref and arydshln, so make sure, these packages are loaded in the mentioned order. Please also clean up wour preamble to make sure you only load packages once. (I already started and commented out some of the duplicates.)

\documentclass[10pt,english, openany, twoside]{book}

\usepackage[table]{xcolor}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Loading packages that alter the style
\usepackage[]{graphicx}
%\usepackage[]{color} %%% not needed. You already load xcolor.
\usepackage{alltt}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\setcounter{secnumdepth}{3}
\setcounter{tocdepth}{3}
\setlength{\parskip}{\smallskipamount}
\setlength{\parindent}{0pt}

% Set page margins
\usepackage[top=1in, bottom=1in, left=1in, right=1in]{geometry}

% Package used for placeholder text
\usepackage{lipsum}

% Prevents LaTeX from filling out a page to the bottom
\raggedbottom

% Adding both languages
\usepackage[english]{babel}

% All page numbers positioned at the bottom of the page
\usepackage{fancyhdr}

\pagestyle{fancy}

\renewcommand{\headrulewidth}{0.0pt}

\fancyhead[LE,RO]{}
\fancyhead[RE,LO]{}
\fancyhead[CE,CO]{}
\fancyfoot[CE,CO]{\thepage}


% Adds table captions above the table per default
\usepackage{float}
%\floatstyle{plaintop}
%\restylefloat{table}

% Adds space between caption and table
\usepackage{caption}
\captionsetup[table]{position=bottom}


%Document Styling% <---------%
%%%%%%%%%%%%%%%%%%

\usepackage{float}
\usepackage{array}
\usepackage{hhline} 
%\usepackage{caption} % already loaded
\usepackage{subcaption}
\usepackage{framed}
\usepackage{mdframed} % This frames the sections. However, a command \begin{mdframed}[options] is needed
\usepackage{multicol} % To change column separation use: \setlength{\columnsep}{-3in}
\usepackage{enumitem} % This package removes the indent on the enumeated list. Allows for the command [Leftmargin=*]

%%%%%%%%%%%%%%%%%%


%Graphics% <---------%
%%%%%%%%%%

\usepackage{graphicx} % already loaded
\usepackage{tikz}
\usetikzlibrary{calc}
%\usepackage{xcolor} % already loaded.

%%%%%%%%%%


%Font% <---------%
%%%%%%

%\usepackage[T1]{fontenc} % already loaded before
\usepackage{textcomp} % 
\usepackage{hyperref}
\hypersetup{hidelinks,linkcolor = black} 
\usepackage{url}
\urlstyle{same}

%%%%%%


%Mathematics% <---------%
%%%%%%%%%%%%%

\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsthm} 
\usepackage{physics}
\usepackage{siunitx} 

%For Table%
%%%%%%%%%%%

\usepackage{booktabs}

\sisetup{
    round-mode          = places, % Rounds numbers
    round-precision     = 2, % to 2 places
}
%\usepackage{colortbl} % already loaded by \usepackage[table]{xcolor}
\usepackage{xfrac}

\definecolor{Gray}{gray}{0.85}

\usepackage{longtable} % make sure to load longtable before arydshln!

%dashed line
\usepackage{arydshln}
\setlength\dashlinedash{0.2pt}
\setlength\dashlinegap{1.5pt}
\setlength\arrayrulewidth{0.3pt}

\definecolor{codegray}{gray}{0.9}



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Starts the document
\begin{document}
    

        \begin{longtable}{llll}
                \caption{Serial Command List}
        \label{tab:command-list} \\
            \toprule
            \multicolumn{4}{c}{\textbf{Serial Command List}} \\
            \toprule
            \textbf{Name} & \textbf{Command} & \textbf{Reply} & \textbf{Description} \\
            \midrule
            \endfirsthead
            \bottomrule
            \endlastfoot
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \begin{tabular}{@{}r@{\;}l@{}} 
                                                            n = & power percentage\\
                                                                & \textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                                                            e.g.& \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                                                            r = & ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            \hdashline
            %
            Set Power & \texttt{\$P,n}  & \texttt{\$Pr} & \noindent\begin{tabular}{@{}l} 
                n = power percentage\\
                \phantom{n = }\textbf{Note}: Up to 3 digits and 2 decimal places. \\\\
                
                e.g. \colorbox{codegray}{\texttt{\$P,57.5}} sets power to 57.5\% \\\\
                
                r = ERROR CODE (0 if no error)
            \end{tabular} \\
            %
        \end{longtable} 
    

\end{document}