byteswap() method: Tell *what* exception gets raised when the type
cannot be byteswapped.
diff --git a/Doc/lib/libarray.tex b/Doc/lib/libarray.tex
index cfc9cec..84b2812 100644
--- a/Doc/lib/libarray.tex
+++ b/Doc/lib/libarray.tex
@@ -78,8 +78,9 @@
\begin{methoddesc}[array]{byteswap}{x}
``Byteswap'' all items of the array. This is only supported for
-integer values. It is useful when reading data from a file written
-on a machine with a different byte order.
+integer values; for other types of values, \exception{RuntimeError} is
+raised. It is useful when reading data from a file written on a
+machine with a different byte order.
\end{methoddesc}
\begin{methoddesc}[array]{fromfile}{f, n}