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diff --git a/src/boost/libs/histogram/examples/guide_fill_profile.cpp b/src/boost/libs/histogram/examples/guide_fill_profile.cpp
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+++ b/src/boost/libs/histogram/examples/guide_fill_profile.cpp
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+// Copyright 2019 Hans Dembinski
+//
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt
+// or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+//[ guide_fill_profile
+
+#include <boost/format.hpp>
+#include <boost/histogram.hpp>
+#include <cassert>
+#include <iostream>
+#include <sstream>
+#include <tuple>
+
+int main() {
+  using namespace boost::histogram;
+
+  // make a profile, it computes the mean of the samples in each histogram cell
+  auto h = make_profile(axis::integer<>(0, 3));
+
+  // mean is computed from the values marked with the sample() helper function
+  h(0, sample(1)); // sample goes to cell 0
+  h(0, sample(2)); // sample goes to cell 0
+  h(1, sample(3)); // sample goes to cell 1
+  h(sample(4), 1); // sample goes to cell 1; sample can be first or last argument
+
+  // fills from tuples are also supported, 5 and 6 go to cell 2
+  auto a = std::make_tuple(2, sample(5));
+  auto b = std::make_tuple(sample(6), 2);
+  h(a);
+  h(b);
+
+  // builtin accumulators have methods to access their state
+  std::ostringstream os;
+  for (auto&& x : indexed(h)) {
+    // use `.` to access methods of accessor, like `index()`
+    // use `->` to access methods of accumulator
+    const auto i = x.index();
+    const auto n = x->count();     // how many samples are in this bin
+    const auto vl = x->value();    // mean value
+    const auto vr = x->variance(); // estimated variance of the mean value
+    os << boost::format("index %i count %i value %.1f variance %.1f\n") % i % n % vl % vr;
+  }
+
+  std::cout << os.str() << std::flush;
+
+  assert(os.str() == "index 0 count 2 value 1.5 variance 0.5\n"
+                     "index 1 count 2 value 3.5 variance 0.5\n"
+                     "index 2 count 2 value 5.5 variance 0.5\n");
+}
+
+//]