\usepackage{trimclip}
\fi
-\input{mjo-common}
+\input{mjo-common} % for \of, at least
% Absolute value (modulus) of a scalar.
\newcommand*{\abs}[1]{\left\lvert{#1}\right\rvert}
% The trace of an operator.
\newcommand*{\trace}[1]{ \operatorname{trace}\of{{#1}} }
+% The diagonal matrix whose only nonzero entries are on the diagonal
+% and are given by our argument. The argument should therefore be a
+% vector or tuple of entries, by convention going from the top-left to
+% the bottom-right of the matrix.
+\newcommand*{\diag}[1]{\operatorname{diag}\of{{#1}}}
% The "rank" of its argument, which is context-dependent. It can mean
% any or all of,
% The orthogonal projection of its second argument onto the first.
\newcommand*{\proj}[2] { \operatorname{proj}\of{#1, #2} }
+% The set of all eigenvalues of its argument, which should be either a
+% matrix or a linear operator. The sigma notation was chosen instead
+% of lambda so that lambda can be reserved to denote the ordered tuple
+% (largest to smallest) of eigenvalues.
+\newcommand*{\spectrum}[1]{\sigma\of{{#1}}}
+\ifdefined\newglossaryentry
+ \newglossaryentry{spectrum}{
+ name={\ensuremath{\spectrum{L}}},
+ description={the set of all eigenvalues of $L$},
+ sort=s
+ }
+\fi
+
% The ``Automorphism group of'' operator.
\newcommand*{\Aut}[1]{ \operatorname{Aut}\of{{#1}} }