[Tex/LaTex] How to center align the below subfigure when it stands alone

alignminipagesubcaptionsubfloats

I have three subfigures as shown in the MWE below, I want to align the subfigure c in the center below the two upper figures, how to do that?

\documentclass{scrartcl}
\usepackage{caption}
\usepackage{floatrow}   
\usepackage{subcaption}
\usepackage{graphicx,xcolor} 
\usepackage[framemethod=tikz]{mdframed}

\newcommand{\fakeimage}{{\fboxsep=-\fboxrule\fbox{\rule{0pt}{3cm}\hspace{4cm}}}}

\begin{document}
\begin{figure}
\begin{mdframed}[
  align=center,
  linecolor=black,
  fontcolor=black,
  backgroundcolor=white,
  userdefinedwidth=0.9\textwidth,
  roundcorner=5pt,
  skipabove=0pt,
  skipbelow=0pt,
  leftmargin=0pt,
  innerleftmargin=20pt,
  innerrightmargin=0pt,
  innertopmargin=5pt,
  innerbottommargin=5pt, 
  innerlinewidth=0pt,
  middlelinewidth=0pt,
  outerlinewidth=1pt]
\floatsetup[subfigure]{captionskip=10pt}
%===================== the two upper subfigures ================
\begin{minipage}{.44\textwidth}
    \begin{subfigure}{\linewidth}
    \centering
    \fakeimage
    \caption{Image}\label{fig:image1}
    \end{subfigure}\\[0ex] %
    \qquad
\end{minipage}
\begin{minipage}{.44\textwidth}
    \begin{subfigure}{\linewidth}
    \centering
    \fakeimage
    \caption{Image}\label{fig:image12}
   \end{subfigure}
\end{minipage}%
\vfill
%===================== the one below subfigure ================
\begin{minipage}[c]{.94\textwidth}
  \centering
  \begin{subfigure}{\linewidth}
  \fakeimage
  \caption{Image}\label{fig:image3}
  \end{subfigure} 
\end{minipage}%
\end{mdframed}
\RawCaption{\caption{General caption}
\label{fig:images}}
\end{figure}
\end{document}

which results in:
enter image description here

Best Answer

I wouldn't be using minipage at all; just subfigure is enough.

Code

\documentclass{scrartcl}
\usepackage{caption}
\usepackage{floatrow}   
\usepackage{subcaption}
\usepackage{graphicx,xcolor} 
\usepackage[framemethod=tikz]{mdframed}

\newcommand{\fakeimage}{{\fboxsep=-\fboxrule\fbox{\rule{0pt}{3cm}\hspace{4cm}}}}

\begin{document}
\begin{figure}
\begin{mdframed}[
  align=center,
  linecolor=black,
  fontcolor=black,
  backgroundcolor=white,
  userdefinedwidth=0.9\textwidth,
  roundcorner=5pt,
  skipabove=0pt,
  skipbelow=0pt,
  leftmargin=0pt,
  innerleftmargin=20pt,
  innerrightmargin=0pt,
  innertopmargin=5pt,
  innerbottommargin=5pt, 
  innerlinewidth=0pt,
  middlelinewidth=0pt,
  outerlinewidth=1pt]
\floatsetup[subfigure]{captionskip=10pt}
%===================== the two upper subfigures ================
% \begin{minipage}{.44\textwidth}
    \begin{subfigure}{.44\linewidth}
    \centering
    \fakeimage
    \caption{Image}\label{fig:image1}
    \end{subfigure} %
    \qquad
% \end{minipage}
% \begin{minipage}{.44\textwidth}
    \begin{subfigure}{.44\linewidth}
    \centering
    \fakeimage
    \caption{Image}\label{fig:image12}
   \end{subfigure}
% \end{minipage}%
% \vfill
\\[2ex]
%===================== the one below subfigure ================
% \begin{minipage}[c]{.94\textwidth}
% \centering
  \begin{subfigure}{\linewidth}
  \centering
  \fakeimage
  \caption{Image}\label{fig:image3}
  \end{subfigure} 
% \end{minipage}%
\end{mdframed}
\RawCaption{\caption{General caption}
\label{fig:images}}
\end{figure}
\end{document}

Output

enter image description here

Related Solutions

[Tex/LaTex] captions not appearing below subfigure

You should not put [H] after \begin{subfigure}{\textwidth}[H] Further, these points may be noted:

Don't put a blank line in between the subfigures.
The sum of widths of two subfigure should not exceed \textwidth
Put a % after the first subfigure if you specify a width of 0.5\textwidth for both subfigures. If the sum is less than \textwidth, you may put a \hfill in between.

Now your code:

\documentclass[fleqn,11pt,a4paper,demo]{article}
\usepackage{geometry,array,graphicx,float,caption}
\usepackage{subcaption}

\begin{document}
\begin{figure}[H]
%    \centering
    \begin{subfigure}{0.5\textwidth}
        \centering
        \includegraphics[width=6cm]{initial_normal.eps}
        \caption{Normal Distribution}
        \label{fig1a}
    \end{subfigure}%   %% This % is needed when you use 0.5\textwidth
    %  Don't leave the blank line
    \begin{subfigure}{0.5\textwidth}%[H]   %% Don't put this here
        \centering
        \includegraphics[width=6cm]{initial_uniform.eps}
        \caption{Uniform Distribution}
        \label{fig1b}
    \end{subfigure}
\end{figure}
\end{document}

enter image description here

May be the subcaption package manual is useful here. You can access it by typing texdoc subcaption from command line/prompt. The correct usage for subfigure is

\begin{subfigure}[<pos>]{<width>}

... content like \includegraphics and caption

\end{subfigure}

Here <pos> is t or b c (default). Both [<pos>]{<width>} are same as that for a minipage.

[Tex/LaTex] How to center the subfigure

There's a node which affects the centering, even if it's not visible.

If you don't need the node, remove it.
If you would like to keep the node, add the overlay option so it won't take space:
```
\node[overlay, service, right of= s0, xshift=10mm, text width=3cm] (s10) {};
```

This overlay method is similarly useful for removing such an undesired shifting effect of arrows, so the space they cover won't count.