How come this doesn't change the marker numbering to roman from arabic in Endfloat?
\documentclass[a4paper,12pt,twoside]{book}
\usepackage{graphicx}
\usepackage[nolists]{endfloat}
\renewcommand{\theposttbl}{\Roman{theposttbl}}
\renewcommand{\thepostfig}{\Roman{postfig}}
\begin{document}
\chapter{This is Chapter 1}
Some text in chapter 1. See my figure \ref{fig:MyFigure}.
\begin{figure}
\centering
\includegraphics{histoOne1}
\caption{My caption for this figure}
\label{fig:MyFigure}
\end{figure}
\let\cleardoublepage\clearpage
\chapter{This is Chapter 2}
Some text in chapter 2.
\end{document}