Multiple subfigures not appearing on the same line

Question

Multiple figures under a single caption. I have tried a code to put two images in a together under a same caption. The subfigures do not appear on the same line.

The code is :

    \documentclass{article}
    \usepackage[demo]{graphicx}
    \usepackage{caption}
    \usepackage{subcaption}

\begin{document}
        \blindtext \blindtext \blindtext
    \begin{figure}
            \centering
            \begin{subfigure}[b]{0.5\textwidth}
                    \centering
                    \includegraphics[width=\textwidth]{C:/Thesis/Latex/thesis_1(1)/Figures/study.jpeg}
                                    \rule{35em}{0.3pt}
                    \caption{the distribution of the nodes in the study site}
                    \label{fig:sensor3}
            \end{subfigure}%    <-- % added here
            \hfill %% useful if width of each figure is less the .5\textwidth
            \begin{subfigure}[b]{0.48\textwidth}
                    \centering
                    \includegraphics[width=\textwidth]{C:/Thesis/Latex/thesis_1(1)/Figures/coord.jpeg}
                                    \rule{35em}{0.3pt}
                    \caption{the coordinates of nodes according to the Swiss coordinate system}
                    \label{fig:tiger}
            \end{subfigure}
            \caption{The Grand St. Bernard wireless sensor network deployment} \label{fig:Sensor}
                    \FloatBarrier
    \end{figure}
\end{document}

Problem occurred with the code:

Answer 1

You need to put a % after the first subfigure since the width of each subfigure is .5\textwidth. Also you may need a \hfill if the width is less than .5\textwidth.

\documentclass{article}

\usepackage[demo]{graphicx}
\usepackage{caption}
\usepackage{subcaption}
\begin{document}
\begin{figure}
        \centering
        \begin{subfigure}[b]{0.5\textwidth}
                \centering
                \includegraphics[width=\textwidth]{C:/Thesis/Latex/thesis_1(1)/Figures/study.jpeg}
                \caption{the distribution of the nodes in the study site}
                \label{fig:sensor3}
        \end{subfigure}%    <-- % added here
        \hfill %% useful if width of each figure is less the .5\textwidth
        \begin{subfigure}[b]{0.5\textwidth}
                \centering
                \includegraphics[width=\textwidth]{C:/Thesis/Latex/thesis_1(1)/Figures/study_road.jpeg}
                \caption{the coordinates of nodes according to the Swiss coordinate system}
                \label{fig:tiger}
        \end{subfigure}
        \caption{The Grand St. Bernard wireless sensor network deployment} \label{fig:Sensor}
\end{figure}
\end{document}

But using a width of little less than .5\textwidth (say .49\textwidth) makes it look better IMO.

Edit

Your problem (now) is the \rule{35em}{0.3pt} for which you have put a length of 35em. Actually subfigures are put in a minipage of of specified width. Hence this results in a badbox warning. Use \rule{\textwidth}{0.3pt} (or \linewidth) and badboxes run away.

Also, you are using \FloatBarrier inside the figure environment, which shouldn't be done. Move it outside as in my code.

\documentclass{article}
\usepackage[demo]{graphicx}
\usepackage{caption}
\usepackage{subcaption,placeins,blindtext}

\begin{document}
        \blindtext \blindtext \blindtext
    \begin{figure}
            \centering
            \begin{subfigure}[b]{0.5\textwidth}
                    \centering
                    \includegraphics[width=\textwidth]{C:/Thesis/Latex/thesis_1(1)/Figures/study.jpeg}
                                    \rule{\textwidth}{0.3pt}
                    \caption{the distribution of the nodes in the study site}
                    \label{fig:sensor3}
            \end{subfigure}%    <-- % added here
            \hfill %% useful if width of each figure is less the .5\textwidth
            \begin{subfigure}[b]{0.48\textwidth}
                    \centering
                    \includegraphics[width=\textwidth]{C:/Thesis/Latex/thesis_1(1)/Figures/coord.jpeg}
                                    \rule{\textwidth}{0.3pt}
                    \caption{the coordinates of nodes according to the Swiss coordinate system}
                    \label{fig:tiger}
            \end{subfigure}
            \caption{The Grand St. Bernard wireless sensor network deployment} \label{fig:Sensor}
    \end{figure}
    \FloatBarrier %% put this here.
\end{document}

Answer 2

One of the problems seems to be that you give your \rule commands a fixed width and therefore the subfigures are wider than the stated half \linewidth. I reset the rules to the length of \linewidth which is the width of your subfigures. Above that I put some % sign at the end of the first subfigure environment (Important: there must be no whitespace between the last character and the % sign) to eliminate the space between the two subfigures.

\documentclass{article}
\usepackage{subcaption}
\begin{document}
    \begin{figure}
            \centering
            \begin{subfigure}[b]{0.5\textwidth}
                    \centering
                    \rule{\linewidth}{10em}
            \rule{\linewidth}{0.3pt}
                    \caption{the distribution of the nodes in the study site}
                    \label{fig:sensor3}
            \end{subfigure}%
            \begin{subfigure}[b]{0.5\textwidth}
                    \centering
                    \rule{\linewidth}{6em}
               \rule{\linewidth}{0.3pt}
                    \caption{the coordinates of nodes according to the Swiss coordinate system}
                    \label{fig:tiger}
            \end{subfigure}
            \caption{The Grand St. Bernard wireless sensor network deployment} \label{fig:Sensor}   
    \end{figure}
\end{document}

This gives the following output (I replaced the images by simple \rule commands:

For the subcaptions appearing in the List of Figures: this is a feature of the subcaptions package, not a bug. As far as I could see from the package documentation there is no simple option to turn this off.

Answer 3

I just removed \FloatBarrier and got:

which is what I think you wanted.

Answer 4

I never used subcaption package, but it seems to me that subfigure package can be useful for you.

    \documentclass{article}
    \usepackage{graphicx}

    \usepackage{subfigure}


    \begin{document}
    \begin{figure}

    \subfigure [the distribution of the nodes in the study site] {
        \includegraphics[width=0.5\textwidth]{fig2.jpg}
        %\caption{the distribution of the nodes in the study site}
        \label{fig:sensor3}
    }
    \subfigure[The Grand St. Bernard wireless sensor network deployment]{
        \includegraphics[width=0.5\textwidth]{fig1.jpg}
         \label{fig:tiger}
    }
    \caption{The Grand St. Bernard wireless sensor network deployment}
    \label{fig:Sensor}   

    \end{figure}
    \end{document}

I hope this is useful.