# figure, errors '\undefined control sequence - \ltx@Ifundefined{…'

\documentclass[a4paper,12pt]{article}
\usepackage{graphicx}
\begin{document}
\begin{figure}[htp]
\centering
\includegraphics[width=100mm]{lls.eps}
\hfill
\includegraphics[width=100mm]{AIC.eps}\\
\hfill
\includegraphics[width=100mm]{BIC.eps}\\
\end{figure}
\end{document}


or other code:

\documentclass[a4paper,12pt]{article}
\usepackage{graphicx}
%\usepackage{subfig}
\begin{document}
\begin{figure}
\centering
\label{figur}\caption{equation...}
\begin{tabular}{cp{2cm}c}
\includegraphics[width=60mm]{1.eps}& & \includegraphics[width=60mm]{lls.eps}\\
& & &\\
\includegraphics[width=60mm]{2.eps}& & \includegraphics[width=60mm]{AIC.eps}\\
& & &\\
\includegraphics[width=60mm]{3.eps}& & \includegraphics[width=60mm]{BIC.eps}\\
\end{tabular}
\end{figure}
\end{document}

-
Welcome to tex.sx! If you indent lines by 4 spaces, then they are marked as a code sample. You can also highlight the code and click the "code" button (with "{}" on it). –  Caramdir Jun 1 '11 at 18:15
I cannot reproduce your errors: your code compiles w/o warnings with LaTeX on my computer. –  Marco Lombardi Jun 1 '11 at 18:47
tell us your error message and by the way: \label{figur}\caption{equation...} use it the other way round, first the caption and then the label. Otherwise you'll get wrong references. –  Herbert Jun 1 '11 at 20:17
Are you using latex oder pdflatex? –  Tobi Jun 1 '11 at 20:32
Did you find it out? Do you have an example which reproduces the error? Did installing the oberdiek bundle help? –  Stefan Kottwitz Jun 18 '11 at 17:49

Regarding the error message in the title: I recommend to install or to update the oberdiek bundle. This bundle contains a package ltxcmds.sty, which defines the macro \ltx@IfUndefined. I guess a package you're using relies on a current version of oberdiek and ltxcmds, respectively.