mjo-common: add \Fn for generic fields.

diff --git a/examples.tex b/examples.tex
index c3e22e7d96e4660356020cb9d66aeac0074304a5..7646b66183ec3ce967677147959b6ef195cb1470 100644 (file)
--- a/examples.tex
+++ b/examples.tex
@@ -118,8 +118,10 @@
     superscript when that superscript would be one: $\Nn[1]$,
     $\Zn[1]$, $\Qn[1]$, $\Rn[1]$, $\Cn[1]$. However, if the
     superscript is (say) two, then it appears: $\Nn[2]$, $\Zn[2]$,
-    $\Qn[2]$, $\Rn[2]$, $\Cn[2]$. Finally, we have the four standard
-    types of intervals in $\Rn[1]$,
+    $\Qn[2]$, $\Rn[2]$, $\Cn[2]$. The symbols $\Fn[1]$, $\Fn[2]$,
+    et cetera, are available for use with a generic field.
+
+    Finally, we have the four standard types of intervals in $\Rn[1]$,
     %
     \begin{align*}
       \intervaloo{a}{b} &= \setc{ x \in \Rn[1]}{ a < x < b },\\

diff --git a/mjo-common.tex b/mjo-common.tex
index 041a1eb604a1bb753ba5b8415098d4f310fecc4d..6b357abdbec9b5cdd53dd4c037d2d2e67375432b 100644 (file)
--- a/mjo-common.tex
+++ b/mjo-common.tex
@@ -142,6 +142,19 @@
   }
 \fi
 
+% The n-dimensional product space of a generic field F.
+\newcommand*{\Fn}[1][n]{
+  \mathbb{F}\if\detokenize{#1}\detokenize{1}{}\else^{#1}\fi
+}
+
+\ifdefined\newglossaryentry
+  \newglossaryentry{F}{
+    name={\ensuremath{\Fn[1]}},
+    description={a generic field},
+    sort=F
+  }
+\fi
+
 
 % An indexed arbitrary binary operation such as the union or
 % intersection of an infinite number of sets. The first argument is