From 71a07bdf861c922cef4f828a7342febfc14fca0d Mon Sep 17 00:00:00 2001
From: Peter Munch <peterrmuench@gmail.com>
Date: Mon, 9 Mar 2020 07:32:09 +0100
Subject: [PATCH] Step-69: add missing include cmath

---
 examples/step-69/step-69.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/examples/step-69/step-69.cc b/examples/step-69/step-69.cc
index fca2a20386..f0d4744c25 100644
--- a/examples/step-69/step-69.cc
+++ b/examples/step-69/step-69.cc
@@ -82,6 +82,9 @@
 #include <boost/range/irange.hpp>
 #include <boost/range/iterator_range.hpp>
 
+// For std::isnan and std::isinf.
+#include <cmath>
+
 // @sect3{Class template declarations}
 //
 // We begin our actual implementation by declaring all classes with their
-- 
2.39.5