Beamer handouts

During my career I’ve seen great changes in the presentation of lectures and the production of handouts.

The original lecture technology, writing on a blackboard with a piece of chalk, is hopelessly old-fashioned now, though I still prefer it for teaching. It was replaced first by whiteboards, whose pens originally used foul-smelling chemicals (they have improved but I am not convinced they are healthier than chalk). Then came overhead projectors. Originally these tried to emulate boards: the acetate was on a roll, and you could turn the handle as you went and write continuous text, and could scroll back (the word seems more fitting for this than for a computer screen). Now OHPs are a health hazard: not, as you might think, because you might injure your back picking them up from the floor, or because you might trip over the lead, but because you might walk through the beam and damage your eyes.

Currently, computer and data projector rule, until they are superseded by the next thing, which might be some sort of smart paper. Mathematicians like the current set-up because the Beamer package gives us access to all the facilities and power of LaTeX.

What about the production of lecture notes or handouts?

I’ve always regarded lecture notes as not identical to what I write on the board or display on the screen, and write them with some care. But this effort, while fine for teaching, is not always appropriate. For seminars or conference presentations, a copy of the slides might be better.

Technology has changed things here as well. Once, lecture notes were handwritten or typed onto stencils, and duplicated by machines using even more unpleasant chemicals. Then came the photocopier, which took the pain out of duplication; high-quality laser printers and LaTeX did the same for preparation.

But reproducing slides has always posed problems of its own. By their nature, they are large format, one slide to a page (or many, if you use Beamer, since each \pause command starts a new page in the PDF). There was a program called mpage which took your PostScript slides and put them four (or two or eight) to a page. To produce PostScript from LaTeX, the standard route was via DVI. But now I only use pdfLaTeX, so this is not immediately viable. You can convert PDF to PostScript by the “print to file” command, and re-convert to PDF using ps2pdf.

The gap was filled, for a time, by various packages (my colleague Peter Kropholler produced one) which took the input file for the sldes and printed it out as a continuous document. Indeed, there is a package called beamerarticle which does this for Beamer input. This is how I produced the notes for my previous LTCC intensive course onSynchronization, which you can find here.

But recently I have found that there is a way to print the Beamer slides as a handout; I shall probably use this method for this month’s LTCC intensive on Laplacian eigenvalues and optimality. This may be useful to others, so here are the details.

The first step is to persuade Beamer to print one frame to a page, ignoring the \pausecommand and its refinements. This is easily done with the option handout. So if you compile your document with first line

\documentclass[12pt,handout]{beamer}

you will have taken this step.

To put several slides on a page, the versatile pdfpages package is what you need. Make a LaTeX input file using this package which has a single line between \begin{document}and \end{document}, reading

\includepdf[<options>]{file.pdf}

where file.pdf is the output from the previous step. Options include page layout (landscape or not, number of slides across and down, spacing, whether they are framed). I recommend you to this page; I have used it as is, except for putting six rather than four slides on a page.

I re-did my Lisbon lecture slides this way: take a look here.

Only one small problem remains. If you called the file that invokes pdfpages something generic like handout.tex, then of course the output will be called handout.pdf. I would prefer to have a name based on that of the input PDF. Probably someone has already done this; but when I am not so busy (maybe when I retire) I might try to produce my own.

[Reposted from Peter Cameron’s Blog]

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