eps file issues in latex

EPS file is the most commonly used figure type in latex.

Two issues involved:
1. Decide bounding box and output a neat graph.
Use the shell program here to get it done: http://www.gnuplot.info/scripts/files/fixbb

2.Solve the eps-pdflatex conflict.
If you want to directly generate pdf file from tex file. Add following lines:
\usepackage{epstopdf}
before your:
\begin{document}

Also, simply use command: pdflatex -shell-escape yourfile.tex to compile your tex file. Final pdf will be built.
The reason is it will automatically generate yourgraph.pdf and use it in your tex file.