How do I get my subsection to not appear bold and with no period at the end?

Question

This is what I have for my codes:

\section{MAIN RESULTS}
\subsection{Graphical Analysis}

I am getting this in the pdf:

Instead I want the subsection in Italic non-bold form with no period at the end.

This is what I have in my preamble:

\documentclass[11pt,reqno]{amsart}

% Packages
\usepackage{graphicx}
\usepackage{amssymb,amsthm}
\usepackage{natbib}
\bibpunct{(}{)}{;}{;}{,}{,}
\usepackage{xr-hyper}
\usepackage[
  colorlinks=true,
  citecolor=blue,
  urlcolor=blue,
  linkcolor=blue
]{hyperref}
\usepackage{bm}
\usepackage{fullpage}
\usepackage{ amssymb }
\usepackage{caption} \captionsetup[figure]{labelfont=normalfont,labelsep=colon}
\usepackage{mathabx}

\pagestyle{plain}

\setlength{\parskip}{\baselineskip}
\setlength{\parindent}{12pt}

\setcounter{secnumdepth}{2}

\allowdisplaybreaks[4]

% Commenting/debugging
\let\IG\iffalse
\let\ENDIG\fi

%% Shortcuts
\newcommand{\td}[2]{\dfrac{d #1}{d #2}}
\newcommand{\std}[2]{\dfrac{d^2 #1}{d {#2}^2}}
\newcommand{\ctd}[3]{\dfrac{d^2 #1}{d #2 d #3}}

\newcommand{\pd}[2]{\dfrac{\partial #1}{\partial #2}}
\newcommand{\spd}[2]{\dfrac{\partial^2 #1}{\partial {#2}^2}}
\newcommand{\cpd}[3]{\dfrac{\partial^2 #1}{\partial #2 \partial #3}}

\newcommand{\pdi}[2]{\partial #1/\partial #2}

\newcommand{\LR}{\Leftrightarrow}
\newcommand{\Lg}{\mathcal{L}}
\newcommand{\half}{\tfrac{1}{2}}
\newcommand{\eqp}{\phantom{=}}
\newcommand{\eqs}{\buildrel s \over =}
\newcommand{\me}{\mathrm{e}}

Answer 1

The formatting you are trying to change was tailored by the AMS to suit its editorial style; since AMS document classes do things in their own way, such changes cannot be made using packages that would cooperate with standard classes and some redefinitions of internal commands will be required.

Redefining \subsection you can get non-bolded, italics font for subsections; a redefinition of \@sect to suppress \@addpunct. will kill the final period.

The code:

\documentclass{amsart}

\makeatletter
\def\subsection{\@startsection{subsection}{1}%
  \z@{.5\linespacing\@plus.7\linespacing}{-.5em}%
  {\normalfont\itshape}}
\def\@sect#1#2#3#4#5#6[#7]#8{%
  \edef\@toclevel{\ifnum#2=\@m 0\else\number#2\fi}%
  \ifnum #2>\c@secnumdepth \let\@secnumber\@empty
  \else \@xp\let\@xp\@secnumber\csname the#1\endcsname\fi
  \@tempskipa #5\relax
  \ifnum #2>\c@secnumdepth
    \let\@svsec\@empty
  \else
    \refstepcounter{#1}%
    \edef\@secnumpunct{%
      \ifdim\@tempskipa>\z@ % not a run-in section heading
        \@ifnotempty{#8}{.\@nx\enspace}%
      \else
        \@ifempty{#8}{.}{.\@nx\enspace}%
      \fi
    }%
    \@ifempty{#8}{%
      \ifnum #2=\tw@ \def\@secnumfont{\bfseries}\fi}{}%
    \protected@edef\@svsec{%
      \ifnum#2<\@m
        \@ifundefined{#1name}{}{%
          \ignorespaces\csname #1name\endcsname\space
        }%
      \fi
      \@seccntformat{#1}%
    }%
  \fi
  \ifdim \@tempskipa>\z@ % then this is not a run-in section heading
    \begingroup #6\relax
    \@hangfrom{\hskip #3\relax\@svsec}{\interlinepenalty\@M #8\par}%
    \endgroup
    \ifnum#2>\@m \else \@tocwrite{#1}{#8}\fi
  \else
  \def\@svsechd{#6\hskip #3\@svsec
    \@ifnotempty{#8}{\ignorespaces#8\unskip
       %\@addpunct.
       }%
    \ifnum#2>\@m \else \@tocwrite{#1}{#8}\fi
  }%
  \fi
  \global\@nobreaktrue
  \@xsect{#5}}
\makeatother

\begin{document}

\section{MAIN RESULTS}
\subsection{Graphical Analysis}

\end{document}

A patch can reduce the code:

\documentclass{amsart}
\usepackage{etoolbox}

\makeatletter
\def\subsection{\@startsection{subsection}{1}%
  \z@{.5\linespacing\@plus.7\linespacing}{-.5em}%
  {\normalfont\itshape}}
\patchcmd{\@sect}
  {\@addpunct.}
  {}
  {}
  {}
\makeatother

\begin{document}

\section{MAIN RESULTS}
\subsection{Graphical Analysis}

\end{document}

Answer 2

Here's a solution that's based on loading the etoolbox package and executing its \patchcmd macro a couple of times.

\documentclass[11pt,reqno]{amsart}

\usepackage{etoolbox}
\makeatletter
\patchcmd{\subsection}{\bfseries}{\itshape}{}{}
\patchcmd{\@sect}{\@addpunct.}{}{}{}
\makeatother

\begin{document}
\setcounter{section}{2} % just for this example
\section{Main Results}
\subsection{Graphical Analysis}
\end{document}