# In LyX, AMSMath module, how to adjust space between examples, theorems, etc.?

In LyX, how would I globally adjust the space between examples, theorems, etc.?

Is there some relatively short command I can add to my preamble?

Image above taken from PDF generated by LyX file, converted into the following LaTeX (plain):

%% LyX 2.2.3 created this file.  For more info, see http://www.lyx.org/.
%% Do not edit unless you really know what you are doing.
\documentclass[english]{article}
\usepackage[T1]{fontenc}
\usepackage[latin9]{inputenc}
\setlength{\parskip}{\bigskipamount}
\setlength{\parindent}{0pt}
\usepackage{amsmath}
\usepackage{amsthm}

\makeatletter
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Textclass specific LaTeX commands.
\theoremstyle{plain}
\newtheorem{thm}{\protect\theoremname}
\theoremstyle{definition}
\newtheorem{example}[thm]{\protect\examplename}

\makeatother

\usepackage{babel}
\providecommand{\examplename}{Example}
\providecommand{\theoremname}{Theorem}

\begin{document}
\begin{example}
Hello.
\end{example}

\begin{example}
Hello.
\end{example}

\begin{thm}
Hello.
\end{thm}

\begin{thm}
Hello.
\end{thm}

\end{document}


Other than redefining the theorem styles, with thmtools for instance you can change the value of \topsep. Such a modification seem to change its value only for theorem-like structures, but I didn't test thoroughly. So I suggest this small addition to your code (value to be adjusted to your needs – I exaggerated the modification for demonstration purposes):

\documentclass[english]{article}
\usepackage[T1]{fontenc}
\usepackage[latin9]{inputenc}
\setlength{\parskip}{\bigskipamount}
\setlength{\parindent}{0pt}
\usepackage{amsmath}
\usepackage{amsthm}

\makeatletter
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Textclass specific LaTeX commands.
\theoremstyle{plain}
\newtheorem{thm}{\protect\theoremname}
\theoremstyle{definition}
\newtheorem{example}[thm]{\protect\examplename}
\topsep = 1cm
\makeatother
\usepackage{babel}
\providecommand{\examplename}{Example}
\providecommand{\theoremname}{Theorem}

\begin{document}

\begin{example}
Hello.
\end{example}

\begin{example}
Hello.
\end{example}

\begin{thm}
Hello.
\end{thm}

\begin{thm}
Hello.
\end{thm}

\end{document}