How to pdflatex a file that incorporates encapsulated Postscript graphics

Let's take a sample EPS file (triangle.eps) 
%!PS-Adobe-3.0  EPSF-3.0
%%BoundingBox: 25 0 75 30
newpath
25 0 moveto
75 0 lineto
40 30 lineto
closepath
stroke
showpage
and a sample LaTex file (triangledrawing.tex) 
\documentclass[12pt]{article}
\usepackage{graphicx}
\begin{document}
 This is a postscript figure

 \includegraphics{triangle.eps}
\end{document}
This file is successfully LaTeXed into triangledrawing.dvi. However the command 
pdf triangledrawing
results in the error message: 
 Unknown graphics extension: .eps.

Solution

  1. Convert an eps graphics file into a pdf file using the command 
     ps2pdf triangle.eps triangle.pdf
  2. Edit the LaTeX file into the following: 
    \documentclass[12pt]{article}
\ifx\pdftexversion\undefined  % in the case of `latex' command
  \usepackage[dvips]{graphics}
  \usepackage[dvips]{color}
\else                         % in the case of `pdflatex' command
  \usepackage[pdftex]{graphics}
  \usepackage[pdftex]{color}
\fi
\begin{document}
   This is a postscript figure 

\ifx\pdftexversion\undefined 
                  % no action
                  % standard latex processing requires no position adjustment
  
\else 
\vspace*{-750pt}  % pdflatex requires a vertical adjustment of graphics            
                  % - unfortunately different in different cases 
\fi                         

\includegraphics{triangle}   % Do not specify extension!
                            % The program will automatically choose whether to use
                            % `triangle.eps' or `triangle.pdf'

\end{document}

Do we need this at all?

Maybe not. After all, a dvi can be converted to a pdf using the commands dvips, ps2pdf (or similar, depending on the system) However, one situation where pdflatexed file seems to work better (in my experience) is a slide presentation.

Author: Dr. Sergey Sadov (Dept.of Mathematics and Statistics, Memorial University of Newfoundland), serge dot sadov at google dot com