floatssubfloats
I have two images that I would like to appear on the same page. Each figure should appear as a separate figure with its own caption.
My problem is that LaTeX sometimes places the figures on separate pages.
I currently have achieved this by putting two \psfragfig commands consecutively within the same figure environment. This seems a simple and succesful approach, but I wonder if I am not using the figure environment correctly by doing this. Should I use the subcaption package instead?
I gather that the figure should be at the very top of a page, to be followed immediately by the table environment. (Moreover, I'm taking for granted that the two environments will actually fit on a single page, right?)
You could achieve these objectives by loading the afterpage package and "encasing" the figure and table environments in an \afterpage{...} statement, as is shown in the following code fragment:
\afterpage{% % defer execution until the next page break occurs anyway
\begin{figure}[t!] % not "pt"
\centering
% remaining contents of figure environment
\end{figure}
\begin{table}[h!] % not t or b or p
\centering
% remaining contents of table environment
\end{table}
} % end of argument of `\afterpage` command
I'm further assuming that there are no deferred figure and/or table environments already waiting to be typeset. If that were the case, you should issue a \clearpage instruction as the very first item in the argument of the \afterpage command. (Even if there are no accumulated deferred floats to take care of, there's no harm done by issuing a \clearpage instruction anyway at the start of the \afterpage material; it would simply be ignored by TeX.)
In addition, if the figure and table environments combined take up most of the page (say, more than 75% of the page), you may also want to issue a second \clearpage instruction, following the end of the table environment. This will tell LaTeX that you want to have just those two floats on the page in question.
Using minipages and a new counter you can produce your subfigures without any packages at all; you can also define a command to provide subcaptions:
\documentclass[twocolumn]{article}
\usepackage{graphicx}
\usepackage{lipsum}
\usepackage{chngcntr}
\newcounter{mysfig}
\counterwithin{mysfig}{figure}
\renewcommand\themysfig{\thefigure(\alph{mysfig})}
\makeatletter
\newcommand\Scaption[1]{%
\refstepcounter{mysfig}%
\vskip.5\abovecaptionskip
\sbox\@tempboxa{\small\themysfig~#1}%
\ifdim \wd\@tempboxa >\hsize
\small\themysfig~#1\par
\else
\global \@minipagefalse
\hb@xt@\hsize{\hfil\box\@tempboxa\hfil}%
\fi
\vskip\belowcaptionskip}
\makeatother
\begin{document}
\lipsum[1-2]
\begin{figure*}
\stepcounter{figure}
\begin{minipage}[t]{\columnwidth}
\begin{minipage}[b]{\columnwidth}
\includegraphics[width=\linewidth]{example-image-a}\par
\end{minipage}
\Scaption{this is the caption for the left subfigure}
\label{sfig:testa}
\end{minipage}\hfill
\begin{minipage}[t]{\columnwidth}
\begin{minipage}[b]{\columnwidth}
\includegraphics[width=\linewidth]{example-image-b}
\end{minipage}
\Scaption{this is the caption for the right subfigure, spanning two lines}
\label{sfig:testb}
\end{minipage}%
\end{figure*}
\lipsum[1-5]
References to subfigures~\ref{sfig:testa} and~\ref{sfig:testb}
\end{document}
Best Answer
You are using the
figureenvironment correctly. The environment is merely a floating shell that primarily contains figure-related content. Sure you can put a table inside of it, but most people include an image and some text (in the form of a caption). If you include more than one, it's just the same:The gap between consecutive floats is given by
\floatsep.One would only use
\subcaptionif you have the same main content you want to illustrate, but the two figure resemble slight variations of one another. So, they should fit under/above the same heading (\caption), but each with a sub-numbering (\subcaption).