{mjo-linear_algebra,examples}.tex: add the derivations Der(V) on V

diff --git a/examples.tex b/examples.tex
index 09df72bf5972e958d029315db02bde7b521a14f6..9096b70a6b11580ba2d611acb80a58948670c98c 100644 (file)
--- a/examples.tex
+++ b/examples.tex
@@ -253,6 +253,9 @@
       \oplus \oplusperp \oplus \oplusperp
     \end{align*}
     \normalsize
+
+    If $V$ is an algebra, then $\Der{V}$ is the space of all
+    (linear) derivations on $V$.
   \end{section}
 
   \begin{section}{Listing}

diff --git a/mjo-linear_algebra.tex b/mjo-linear_algebra.tex
index b85a7102ce447915a46945a6cb7704b25db91d71..062121f6bd33cf879f3b9f4d204334f358f8d1b1 100644 (file)
--- a/mjo-linear_algebra.tex
+++ b/mjo-linear_algebra.tex
@@ -186,4 +186,14 @@
 \fi
 
 
+% The space of all (linear) derivations on its argument, an algebra.
+\newcommand*{\Der}[1]{\operatorname{Der}\of{#1}}
+\ifdefined\newglossaryentry
+  \newglossaryentry{Der}{
+    name={\ensuremath{\Der{V}}},
+    description={the space of all (linear) derivations on $V$},
+    sort=Der
+  }
+\fi
+
 \fi