# [Tex/LaTex] Writing Roman numbers in Equation

roman numeralstex-core

What is the command for writing roman numerals like I, II, IV etc. in an equation ? To be noted that my requirement is to write them within $$…$$ and not as counters or page numbers. Any light on this would be extremely helpful.

If you don't want to do the conversion,

\documentclass{article}
\usepackage{amsmath}

\newcommand{\RN}[1]{%
\textup{\uppercase\expandafter{\romannumeral#1}}%
}

\begin{document}
$\RN{4}+\RN{12}=\RN{16}$
\end{document}


If you also don't want to do the arithmetic

\documentclass{article}
\usepackage{amsmath}
\usepackage{xparse}

\ExplSyntaxOn
\NewDocumentCommand{\RN}{m}
{
\textup{ \int_to_Roman:n { #1 } }
}
\ExplSyntaxOff

\begin{document}
$\RN{4}+\RN{12}=\RN{4+12}$
\end{document}