%% diag-s3.tex,  version 30/05/22

%% to LaTeX typeset use <shift><command>L 
%% to run BibDesk use:  <shift><command>B

\documentclass[11pt,a4paper]{article}
\usepackage[utf8]{inputenc}

%\usepackage{latexsym,amssymb,amsmath,enumerate,theorem}
\usepackage[all]{xy}

\setlength{\textwidth}{11cm}
\setlength{\textheight}{9cm}
\setlength{\topmargin}{0pt}
\setlength{\headsep}{0pt}
\setlength{\headheight}{0pt}
\setlength{\oddsidemargin}{0pt}
\setlength{\evensidemargin}{0pt}

\thispagestyle{empty}

%\input{newcomm}   %%% file of \newcommand's

\begin{document}

% p.29 
$$
\xy
\xymatrix{
   & & & & gf \ar@{-->}@/_2ex/[dd]^(0.6){g} \ar@{-->}[ddddddrrrr]_{f} 
           & & & & \\
   & & & & & & & & \\ 
   & & & & F \ar[llddd]^{f} \ar@{-->}@/_2ex/[uu]^(0.6){g}
           & & & & \\
   & & & & & & & & \\ 
   & & & &  & & & & \\
   & & {\rm id} \ar[rrrr]^{f} \ar@/_2ex/[lld]^(0.6){g}
       & & & & f \ar@{-->}[lluuu]^{f} \ar@/_2ex/[rrd]^(0.6){g}
               & & \\ 
   g \ar[uuuuuurrrr]^{f} \ar@{-->}@/_2ex/[rru]^(0.6){g}
   & & & & & & & & fg \ar@{-->}[llllllll]^{f} \ar@{-->}@/_2ex/[llu]^(0.6){g}\\ 
}
\endxy
$$

\end{document}
