# Driver-dependent invocations of the graphix package?

The LaTeX General Guidelines show a conditional invocation of the graphicx package. I wanted to test this out. I did the following:

1. Created a main.tex in which I LEFT OUT the big, complicated, conditional header linked above
2. Included a myplot.pdf and myplot.eps in my working directory.
3. Included a call to \includegraphics{myplot} in my main.tex.
4. Ran TeXify. myplot.eps was plotted as desired.
5. Ran PdfTeXify. myplot.pdf was plotted as desired.

Q: Considering that my steps above worked perfectly fine, what's the point of the big, complicated, conditional header?

Q: Do pdftex and dvips really need to be passed as options to \documentclass and \usepackage{graphicx}?

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Your method is the approach recommended in the FAQ, see this answer. –  Lev Bishop Feb 27 '11 at 22:46

This kind of conditional header is outdated (IMHO). I learned it as beginner as well and stopped using it with the same results as you. The graphicx package is normally very well capable to detect the output driver by itself. This is in most cases even better than hard coding it.
Because pdflatex is nowadays also used for DVI output simply checking for the existence of \pdfoutput is not enough anymore. If you need this use the ifpdf package which provides the \ifpdf switch. One reason to use it might be to define a different extension list with \DeclareGraphicsExtensions for DVI/PS or PDF output. I stopped supporting both formats with my documents years ago. Normally you chose your format in advance and stick with it. IMHO due to the modern eps-to-pdf packages there is not much reason to use DVI output nowadays.