Btukfyl

I've got three figures that I place vertically on a half page.

begin{figure}

includegraphics[width=0.4textwidth]{images/fig1a.png}

includegraphics[width=0.4textwidth]{images/fig1b.png}

includegraphics[width=0.4textwidth]{images/fig1c.png}

end{figure}

I want to subnumber them and put the (a), (b) and (c) at the corners of the images. All three figures are of different resolutions and sizes. It's hard do that and get them vertically aligned in the resulted pdf. So, my question is if there is a proper tool or package to do this automatically?

Regards
Ilya

There are a few details which can be painful to discover, since some are from the caption manual. The blank lines (par) are needed to keep them from winding up side by side.

You said different sizes. Although the MWE uses known sizes, this will work for images with unknown sizes. subcaptionbox does this automatically (thank you Alex Sommerfelt for pointing this out), but it is no big deal. All subfigures are basically minipages with captions.

documentclass{article}

usepackage[singlelinecheck=off]{subcaption}

usepackage{graphicx}

begin{document}

begin{figure}

centering

subcaptionbox{}{includegraphics[width=0.4textwidth]{example-image-a}}



sbox0{includegraphics[width=0.4textwidth]{example-image-b}}% measure width

begin{subfigure}{wd0}

usebox0

caption{}

end{subfigure}



sbox0{includegraphics[width=0.4textwidth]{example-image-c}}% DIY caption

begin{minipage}{wd0}

leavevmodellap{(c)~}% left

usebox0

(c)

end{minipage}

caption{There is usually one of these too.}

end{figure}

end{document}

These solutions puts the subcaption at the upper right corner.

documentclass{article}

usepackage[singlelinecheck=off,justification=raggedleft,position=top]{subcaption}

usepackage{graphicx}

begin{document}

begin{figure}

centering

subcaptionbox{}{includegraphics[width=0.4textwidth]{example-image-a}}



sbox0{includegraphics[width=0.4textwidth]{example-image-b}}% measure width

begin{subfigure}{wd0}

caption{}

usebox0

end{subfigure}



sbox0{includegraphics[width=0.4textwidth]{example-image-c}}% DIY caption

begin{minipage}{wd0}% in case you want to align side by side

strutmakebox[wd0][r]{(c)}par% above

usebox0%

rlap{raisebox{dimexpr ht0-topskip}{(c)}}% right

end{minipage}



caption{There is usually one of these too.}

end{figure}

end{document}

I think the simplest of all methods is to use the subfigure package, that adjusts to the desired dimensions of your images, althought it has problems with tikz, so I avoid it, but it works wonderfully with imported graphics

documentclass{article}

usepackage{graphicx,subfigure}

begin{document}

begin{figure}

centering

subfigure[Subcaption a.]{includegraphics[width=.6textwidth]{example-image-a}}

subfigure[Subcaption b.]{includegraphics[width=.6textwidth]{example-image-b}}

subfigure[Subcaption c.]{includegraphics[width=.6textwidth]{example-image-c}}

caption{Caption}

end{figure}

end{document}