1

this code 

\documentclass{article}
\makeatletter
\newcommand*{\rom}[1]{\expandafter\@slowromancap\romannumeral #1@}
\makeatother
\begin{document}
Charles's sister Bona, married the eldest son of Philip \rom{6} of France,
the future John \rom{2} of France, in 1335.

Today is the year \rom{2011}.
\end{document}

generates this roman numbers symbol

enter image description here

how to generate the roman numbers symbol in this font/style/format?

enter image description here

whnlp
  • 321
  • I think this is a \mathbb{I}: \documentclass{article} \usepackage{amsfonts} \begin{document} $\mathbb{I}$ \end{document} –  Oct 24 '19 at 01:24
  • @Schrödinger'scat Thanks a lot! Please move your comments to answer, I'll accept it. – whnlp Oct 24 '19 at 01:29

1 Answers1

2

It is a \mathbb{I} that ships with amsfonts.

\documentclass{article}
\usepackage{amsfonts}
\begin{document}
\[ p(h|\mathcal{D})=
\frac{p(h|\mathcal{D})p(h)}{\sum_{h'\in\mathcal{H}} p(h'|\mathcal{D})}=
\frac{p(h)\mathbb{I}(\mathcal{D}\in h)/|h|^N}{%
\sum_{h'\in\mathcal{H}} p(h')\mathbb{I}(\mathcal{D}\in h')/|h'|^N}
\]
\end{document}

enter image description here

It could also be a \mathbbm{I} that requires the bbm package.