NCAR's Geophysical Statistics Project

Institute for Mathematics Applied to Geosciences Institute for Mathematics Applied to Geosciences

[laptop + LaTeX == Presentation]


Introduction

This page collects some examples and tips for producing a high-quality Portable Document Format (PDF) document that is formatted for displaying on an entire PC screen (with something like a 4:3 aspect ratio, the most common ratio). The obvious intent is to use the document for a PC-based presentation (most commonly, a laptop). Since we have no allegiance to any one O/S, we focus on software that is free and available on the WWW for both Windows and UNIX/Linux. With a PDF format file one can give a laptop presentation using the Acrobat viewer.

We show a some examples written in LaTeX with a minimal number of package-specific commands, how to prepare figures so they can be included neatly, how to convert the LaTeX document to PDF, and finally, how to view it.

Since PDF supports "hyperrefs" etc., you should be able to navigate by following links. If you want to get terribly fancy, you can also add a navigation panel so you can zip right to the proper slide in response to the germane question ... The different packages mentioned here have different philosophies about how much of this functionality is supported, and with what amount of difficulty.




LaTeX to PDF -- via PDFLaTeX

[Introduction] [Simple example] [Figures] [Viewing]

Introduction

The one we seem to use most is PDFLaTeX. A nice set of installation instructions and such was written by Matt Welsh. However, we also note that Red Hat and we suspect many other standard versions of LINUX include pdflatex as part of the standard Tex/LaTeX distribution.

PDFLaTeX results in a high-quality pdf document that is formatted for viewing on a PC screen or with a data projector. It directly converts LaTeX to pdf without creating an intermediate dvi file. The obvious intent is to use this file for giving a laptop-based seminar. However, this strategy allows for a printed version (handouts) to be made with minimal changes. Here are some examples written in LaTeX, (with a few extra commands), and a description of how to prepare figures and how to view (present) it. Finally, we note one advantage of PDFLaTeX is that it can incorporate several types of graphics images including jpg and png formats.

A Simple Example

The text file example.tex is a short example that has most of the elements that are used for seminar overhead slides. To try this out, and transfer the files:
example.tex, example.png, visitus914.jpg, gsp2.jpg, pause.sty, ROCK.jpg.

And then (in UNIX/LINUX):

pdflatex example

will create the file example.pdf and can be viewed by acroread (the free Acrobat reader) or the Linux viewer xpdf.

Some LaTeX tips

Figures

Use the /includegraphics command and refer to the example to see how it used. It appears to be standard and more flexible than the psfig command. Unfortunately, ps figures can not be directly included under pdflatex, but see the conversion tips below.

Perhaps an unexpected difficulty that is encountered only occasionally is incorporating a figure that looks "perfectly fine" when printed or viewed in isolation but manages to become distorted when included as part of a presentation. Incorporating figures without distorting the graphic might mean tailoring the figure-producing package or producing the graphic in a different format. Not all formats are supported by the presentation software outlined here. Some packages like PostScript (.ps), some like Encapsulated PostScript (.eps), JPEG, etc... Most commonly, the problem is from an overly-robust Bounding Box in the rendering package. (It has been my experience that many packages simply "draw a big white rectangle" and let you plot on top of that. The rectangle then dictates the extent of the figure, even though your graphic occupies a subset of the region. Configuring the minimally-sufficient plot region from the onset goes a long way toward alleviating problems later.)

We recommend that one draws the figures directly in png, pdf or jpeg format rather create later problems with the conversions from postscript to another format.

At this point, I know of no package available for Windows and Unix/Linux that can incorporate animations/movies. Generally, I have the animation "ready" and simply minimize acroread for a moment, show the animation, and continue.

Creating pdf format figures

Here are some suggestions to convert postscript files or to create plots in R with the intent of including them in your talk.

Creating jpeg format figures

These are great to reduce the size of images. However, typically text is not reproduced well. In UNIX use

convert  -quality 100 fig1.ps fig1.jpg

A more interactive tool for conversion is xv. Setting the quality less than 100 (even just 99) will usually produce a much smaller file but with some loss of clarity. R also has a jpeg function to create jpeg figures directly.

Viewing or giving a presentation

The pdf file that is produced can be viewed easily using Abode Acrobat this is acroread in UNIX/LINUX.



Last modified: Jul 27 2005  by thoar@ucar.edu