Strange problem using landscape, afterpage and split

Question

I have a problem in Latex where \afterpage somehow seems to have problems with a split equation, so that the code does not compile. I use \afterpage to fill a page before a large landscape figure is presented, to avoid the whitespace that is produced otherwise. This is the MWE (comment out the \afterpage command and it will compile):

\documentclass[a4paper]{scrbook}
\usepackage{amsmath, amssymb}
\usepackage{graphicx}
\usepackage{pdflscape}
\usepackage{afterpage}
\usepackage{lipsum}
\begin{document}
\lipsum[1-2][1-20]
\afterpage{
\begin{landscape}
\begin{figure}
\includegraphics[width=\textwidth]{example-image-a}
\caption{Caption}
\end{figure}
\end{landscape}}
\lipsum[1-5]
\begin{equation}
\begin{split}
x&=\frac{\pi}{2}\
&=\frac{3}{2}
\end{split}
\end{equation}
\lipsum[1-2]
\end{document}

why don't you use sidewaystable and let the figure properly float? afterpage is not really a stable command. — Ulrike Fischer, Aug 18 '20 at 12:20
I used sidewaysfigure first, which works perfectly except that the corresponding page in the pdf is not rotated. So far I could achieve this effect only by using the landscape environment. If it is possible to rotate the page in the pdf also with using sidewaystable, this would be perfect! — CarlJacobi, Aug 18 '20 at 12:36
See https://tex.stackexchange.com/a/472608/2388 and https://tex.stackexchange.com/a/479816/2388 (in a future latex it will be easier, but currently you need labels with pdflatex, only lualatex and xelatex can do it without it). — Ulrike Fischer, Aug 18 '20 at 12:40
If you are open to try with another font, try your code with \renewcommand{\rmdefault}{qag} (as an example) in your preamble .... — koleygr, Aug 18 '20 at 12:49
if you use afterpage you should be happy when it works, not surprised when it doesn't. — David Carlisle, Aug 18 '20 at 13:09
@UlrikeFischer Thanks, your solution in the first thread works perfectly if I also include \usepackage[figuresright]{rotating}, as suggested in one of the comments. Otherwise some figures appear upside down in the pdf. — CarlJacobi, Aug 18 '20 at 13:18

John Kormylo · Answer 1 · 2020-08-18T14:55:21.007

An easy solution is to separate the equation from the preceding paragraph. This solution puts the equation inside a splitable paragraph, but the spacing on the first and last lines are slightly off.

\documentclass[a4paper]{scrbook}
\usepackage{amsmath, amssymb}
\usepackage{graphicx}
\usepackage{pdflscape}
\usepackage{afterpage}
\usepackage{lipsum}
\newsavebox{\tempbox}
\begin{document}
\lipsum[1-2]
\afterpage{%
\begin{landscape}
\begin{figure}
\centering
\includegraphics[width=\textheight]{example-image-a}
\caption{Caption}
\end{figure}
\end{landscape}}
\lipsum[1-3]
\setbox\tempbox=\vbox{\strut
Text in pragraph before equation.
Text in pragraph before equation.
Text in pragraph before equation.
Text in pragraph before equation.
Text in pragraph before equation.
Text in pragraph before equation.
Text in pragraph before equation.
\begin{equation}
\begin{split}
x&=\frac{\pi}{2}\
&=\frac{3}{2}
\end{split}
\end{equation}
Text in same paragraph after equation.
}\unvbox\tempbox
\lipsum[1-2]
\end{document}

Strange problem using landscape, afterpage and split

1 Answers1