I have the code below for my table. Everything is okay, but I can not see the horizontal line between the 2nd and 6th columns below the text "Runtime (seconds)", and "Objective Function Value". See the desire table in attachment. Please, help me. Thank you.
Code: Select all
\documentclass[journal]{IEEEtran}
%\documentclass[12pt]{exam}
%\documentclass[twoside, 11pt]{article}
\RequirePackage{amssymb, amsfonts, amsmath, latexsym, verbatim, xspace, setspace}
\usepackage{booktabs}
\usepackage{blkarray}%matrizes com rótulos em linhas e colunas
%\RequirePackage{tikz, pgflibraryplotmarks}
\usepackage[margin=0.7in]{geometry}
\usepackage[english]{babel}
%\usepackage[DM,final,newLogo]{uaThesis}
%\usepackage{fancyhdr}
%\usepackage[table]{xcolor}
%\usepackage{algorithmic}
\usepackage{algorithm}
\usepackage{algpseudocode}
%\usepackage{algcompatible}
\usepackage{colortbl}
\usepackage[long]{optidef}%Problemas de optimização
\usepackage{color}
\usepackage[latin1]{inputenc}
\usepackage{enumerate}
\usepackage{mdframed}%para fazer molduras
\usepackage{lipsum}
\usepackage{array}
\usepackage{multirow}
%\usepackage[table,xcdraw]{xcolor}
\usepackage{xcolor}
\usepackage{enumitem}%melhora o begin description, enumerate e itemize
%\usepackage{bigints}
\usepackage[]{graphicx}%gerir imagens
%\usepackage[export]{adjustbox}
\graphicspath{ {./images/} }%Permite procura as images em pastas de imagens na pasta de trabalho
\usepackage{multicol}%para texto em colunas
\usepackage{lmodern}
\usepackage{float} %gestaoo de posicaoo de figuras
%\floatstyle{boxed} %coloca uma borda fina nas figura
%\restylefloat{figure}%parte da instrução para colocação de borda nas figuras
\usepackage{float} %gestaoo de posicaoo de figuras
%\usepackage{caption}%legenda de figura
\usepackage[justification=justified]{caption}
\usepackage{subcaption}%legendas de subfiguras
\usepackage{indentfirst}
%\usepackage{subfigure}
\usepackage{xcolor}
\usepackage[long]{optidef}
\usepackage{wrapfig}%Permite esccrever texto à volta de figuras
\usepackage{chngcntr}
\counterwithout{figure}{section}%numeração de figuras independente das secções
%\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
%\usepackage{amsmath}
%\usepackage{amsfonts}
%\usepackage{amssymb}
\usepackage{stmaryrd}
%\usepackage{graphicx}
\usepackage[export]{adjustbox}
%\graphicspath{ {./Figuras/} }
%%%%
\usepackage{natbib} %package para a bibliografia
\usepackage{setspace}%espaçamento entre linhas
\usepackage{indentfirst} %permite identar o 1.º paragráfo das secções
\usepackage{url}%mantém os links nos ficheiros PDF
\usepackage{hyperref}%usado para lidar com comandos de referência cruzada em LaTeX para produzir links de hipertexto no documento PDF.
\RequirePackage{pgfcore}
\usepackage{chngcntr}
\usepackage{graphics}
\newcounter{enumr} \renewcommand{\theenumr}{\roman{enumr}}
\providecommand{\sin}{}
\providecommand{\sin}{}
\newenvironment{enumerater}{\begin{list}{(\theenumr)}{\usecounter{enumr}}}{
\end{list}}
\newcommand{\qua}{\hrulefill \hspace{3mm}\fbox{\rule[-0.2cm]{0cm}{0.4 cm} $\;$ } }
\newcommand{\qu}{\fbox{\rule[-0.05cm]{0cm}{0.3 cm} $\;$ } }
\newcommand{\MTL}{{\sc\scriptsize
MATLAB$\textsuperscript{\textregistered}$}}
\DeclareMathOperator{\arctg}{arctg}
\DeclareMathOperator{\arcsec}{arcsec}
\DeclareMathOperator{\arcsen}{arcsen}
\DeclareMathOperator{\arccot}{arccot}
\DeclareMathOperator{\arccsc}{arccosec}
\DeclareMathOperator{\sen}{sen}
\DeclareMathOperator{\tg}{tg}
\DeclareMathOperator{\cotg}{cotg}
\DeclareMathOperator{\cosec}{cosec}
\DeclareMathOperator{\argmin}{argmin}
% EDITAR CABEÇALHO DA PROVA
\algrenewcommand\algorithmicrequire{\textbf{Input:}}%Nos algoritmos, altera Require para Input
\algrenewcommand\algorithmicensure{\textbf{Output:}}%Nos algoritmos, altera Ensure para Input
\setlist{labelindent=\parindent, leftmargin=*}%alinhar itens enumerate e itemize com o paragrafo
\parskip=3.0mm %inser um espaço de x mm entre parágrafos em todo documento
\newtheorem{teo}{Theorem}%[section]
\newtheorem{defin}{Definition}%[section]
\newtheorem{lema}{Lemma}%[section]
\newtheorem{cor}{Corolary}%[section]
\newtheorem{prop}[teo]{Proposition}
%\newtheorem{defin}[teo]{Definition}
\newtheorem{algor}{Algorithm} %[section]
\newtheorem{prob}{Problem}%[section]
\newtheorem{example}{Example}%[section]
\newtheorem{obser}{Observation}%[section]
\newenvironment{prove}{\endsloppypar\noindent\bgroup%\small
{\bf Proof. }}{\samepage\null\hfill $\Box$\endsloppypar\egroup}
\numberwithin{equation}{section}%numerar as equações
\bibliographystyle{plain}
\hyphenation{op-tical net-works semi-conduc-tor}
\begin{document}
\begin{table}[]
\resizebox{\columnwidth}{!}{
\begin{tabular}{|c|ccc|ccc|}
\hline
\rowcolor[HTML]{A6A6A6}
\cellcolor[HTML]{A6A6A6} &
\multicolumn{3}{c|}{\cellcolor[HTML]{A6A6A6}\textbf{Runtime (seconds)}} &
\multicolumn{3}{c|}{\cellcolor[HTML]{A6A6A6}\textbf{Objective Function Value}}\\ \cline{2-7} %\cmidrule{2-7}
\rowcolor[HTML]{A6A6A6}
\multirow{-2}{*}{\cellcolor[HTML]{A6A6A6}\textbf{m}} &
\multicolumn{1}{c|}{\cellcolor[HTML]{A6A6A6}MCL} &
\multicolumn{1}{c|}{\cellcolor[HTML]{A6A6A6}MC-Greedy} &
ClusterGreedy &
\multicolumn{1}{c|}{\cellcolor[HTML]{A6A6A6}Linking set} &
\multicolumn{1}{c|}{\cellcolor[HTML]{A6A6A6}MC-Greedy} &
ClusterGreedy \\ \hline
46 & \multicolumn{1}{c|}{9.63} & \multicolumn{1}{c|}{5686.06} & 1262.49 & \multicolumn{1}{c|}{52} & \multicolumn{1}{c|}{63} & 66 \\ \hline
74 & \multicolumn{1}{c|}{8.49} & \multicolumn{1}{c|}{6102.56} & 1196.61 & \multicolumn{1}{c|}{52} & \multicolumn{1}{c|}{63} & 64 \\ \hline
35 & \multicolumn{1}{c|}{10.47} & \multicolumn{1}{c|}{1842.13} & 2980.89 & \multicolumn{1}{c|}{55} & \multicolumn{1}{c|}{63} & 66 \\ \hline
54 & \multicolumn{1}{c|}{7.18} & \multicolumn{1}{c|}{6448.28} & 639.67 & \multicolumn{1}{c|}{54} & \multicolumn{1}{c|}{64} & 55 \\ \hline
36 & \multicolumn{1}{c|}{9.54} & \multicolumn{1}{c|}{2507.60} & 1066.20 & \multicolumn{1}{c|}{57} & \multicolumn{1}{c|}{63} & 67 \\ \hline
36 & \multicolumn{1}{c|}{19.01} & \multicolumn{1}{c|}{6646.61} & 2257.27 & \multicolumn{1}{c|}{55} & \multicolumn{1}{c|}{64} & 66 \\ \hline
57 & \multicolumn{1}{c|}{11.23} & \multicolumn{1}{c|}{3806.67} & 1519.56 & \multicolumn{1}{c|}{51} & \multicolumn{1}{c|}{62} & 55 \\ \hline
35 & \multicolumn{1}{c|}{18.50} & \multicolumn{1}{c|}{5989.16} & 2059.86 & \multicolumn{1}{c|}{54} & \multicolumn{1}{c|}{64} & 67 \\ \hline
45 & \multicolumn{1}{c|}{11.30} & \multicolumn{1}{c|}{4338.80} & 2404.25 & \multicolumn{1}{c|}{51} & \multicolumn{1}{c|}{63} & 65 \\ \hline
35 & \multicolumn{1}{c|}{11.01} & \multicolumn{1}{c|}{4388.51} & 1660.90 & \multicolumn{1}{c|}{53} & \multicolumn{1}{c|}{63} & 53 \\ \hline
72 & \multicolumn{1}{c|}{10.74} & \multicolumn{1}{c|}{17638.40} & 2538.96 & \multicolumn{1}{c|}{54} & \multicolumn{1}{c|}{64} & 63 \\ \hline
36 & \multicolumn{1}{c|}{10.32} & \multicolumn{1}{c|}{13198.84} & 7031.46 & \multicolumn{1}{c|}{52} & \multicolumn{1}{c|}{64} & 66 \\ \hline
70 & \multicolumn{1}{c|}{9.66} & \multicolumn{1}{c|}{23175.31} & 2869.66 & \multicolumn{1}{c|}{56} & \multicolumn{1}{c|}{64} & 68 \\ \hline
35 & \multicolumn{1}{c|}{42.80} & \multicolumn{1}{c|}{18236.07} & 5720.39 & \multicolumn{1}{c|}{56} & \multicolumn{1}{c|}{64} & 67 \\ \hline
35 & \multicolumn{1}{c|}{10.60} & \multicolumn{1}{c|}{22917.41} & 9670.09 & \multicolumn{1}{c|}{55} & \multicolumn{1}{c|}{65} & 64 \\ \hline
71 & \multicolumn{1}{c|}{17.54} & \multicolumn{1}{c|}{6037.13} & 3432.35 & \multicolumn{1}{c|}{55} & \multicolumn{1}{c|}{64} & 65 \\ \hline
72 & \multicolumn{1}{c|}{11.30} & \multicolumn{1}{c|}{5725.89} & 2709.56 & \multicolumn{1}{c|}{54} & \multicolumn{1}{c|}{63} & 66 \\ \hline
35 & \multicolumn{1}{c|}{10.68} & \multicolumn{1}{c|}{5859.43} & 6857.45 & \multicolumn{1}{c|}{55} & \multicolumn{1}{c|}{64} & 66 \\ \hline
63 & \multicolumn{1}{c|}{12.22} & \multicolumn{1}{c|}{6199.05} & 1544.76 & \multicolumn{1}{c|}{56} & \multicolumn{1}{c|}{64} & 68 \\ \hline
71 & \multicolumn{1}{c|}{11.39} & \multicolumn{1}{c|}{5965.02} & 1079.90 & \multicolumn{1}{c|}{54} & \multicolumn{1}{c|}{64} & 68 \\ \hline
\end{tabular}
}
%\caption{Computational results for $n=3000$, $k=30$, $r=50$ (from $ 1^{st} $ to $ 10^{th} $ experiments), and $r=100$ (from $ 11^{th} $ to $ 20^{th} $ experiments).}
% \label{tab3000}
\end{table}
\end{document}
minimal working example