How to add dot after \section number in headline and ToC, without adding dot to \ref command

Question

I need \section (\subsection, \subsubsection ...) titles printed with dot after numbering.

Example:

1. My Title

For this purpose i use:

\renewcommand\thesection{\normalfont \arabic{section}.}

\renewcommand\thesubsection{\thesection\arabic{subsection}.}

\renewcommand\thesubsubsection{\thesubsection\arabic{subsubsection}.}

\renewcommand\theparagraph{\thesubsubsection\arabic{paragraph}.}

But this method also adds extra dot to \ref{} commands. So code "Look at section \ref{section:label}." produces string "Look at section 3.."

Is there any way to add dot only to headlines and ToC, but not to references?

Answer 1

Here is how to do with titlesec/titletoc. The dot after the label is added by \titleformat, not by \thesection. As for the dot in the table of contents, it is an option in titletoc. In addition, I use cleveref for a simpler writing of cross-references.

\documentclass[12pt]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{heuristica}
\usepackage{lipsum}
\usepackage{titlesec}
\usepackage[dotinlabels]{titletoc}
\titleformat{\section}[hang]{\bfseries\large}{Section \thesection.}{0.4em}{}
\titlespacing*{\section}{0pt}{2\baselineskip}{2\baselineskip}
\dottedcontents{section}[3.8em]{}{2.3em}{1pc}
\usepackage{cleveref}
\begin{document}
\tableofcontents
\section{Preliminaries}\label{sec:prelim}
\lipsum[1]
\section{Another section}
See \Cref{sec:prelim}.
\end{document} 

Answer 2

\usepackage{titlesec}
\titlelabel{\thetitle.\quad}

More information in the titlesec package documentation on page 3.