Adding upstream version 14.2.21.upstream/14.2.21upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 62 insertions, 0 deletions

diff --git a/src/boost/libs/histogram/examples/guide_axis_growing.cpp b/src/boost/libs/histogram/examples/guide_axis_growing.cpp
new file mode 100644
index 00000000..5aed481b
--- /dev/null
+++ b/src/boost/libs/histogram/examples/guide_axis_growing.cpp
@@ -0,0 +1,62 @@
+// 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)
+
+// clang-format off
+
+//[ guide_axis_growing
+
+#include <boost/histogram.hpp>
+#include <cassert>
+
+#include <iostream>
+
+int main() {
+  using namespace boost::histogram;
+
+  // make a growing regular axis
+  // - it grows new bins with its constant bin width until the value is covered
+  auto h1 = make_histogram(axis::regular<double,
+                                         use_default,
+                                         use_default,
+                                         axis::option::growth_t>{2, 0., 1.});
+  // nothing special happens here
+  h1(0.1);
+  h1(0.9);
+  // state: [0, 0.5): 1, [0.5, 1.0): 1
+  assert(h1.axis().size() == 2);
+  assert(h1.axis().bin(0).lower() == 0.0);
+  assert(h1.axis().bin(1).upper() == 1.0);
+
+  // value below range: axis grows new bins until value is in range
+  h1(-0.3);
+  // state: [-0.5, 0.0): 1, [0, 0.5): 1, [0.5, 1.0): 1
+  assert(h1.axis().size() == 3);
+  assert(h1.axis().bin(0).lower() == -0.5);
+  assert(h1.axis().bin(2).upper() == 1.0);
+
+  h1(1.9);
+  // state: [-0.5, 0.0): 1, [0, 0.5): 1, [0.5, 1.0): 1, [1.0, 1.5): 0 [1.5, 2.0): 1
+  assert(h1.axis().size() == 5);
+  assert(h1.axis().bin(0).lower() == -0.5);
+  assert(h1.axis().bin(4).upper() == 2.0);
+
+  // make a growing category axis (here strings)
+  // - empty axis is allowed: very useful if categories are not known at the beginning
+  auto h2 = make_histogram(axis::category<std::string,
+                                          use_default,
+                                          axis::option::growth_t>());
+  assert(h2.size() == 0); // histogram is empty
+  h2("foo"); // new bin foo, index 0
+  assert(h2.size() == 1);
+  h2("bar"); // new bin bar, index 1
+  assert(h2.size() == 2);
+  h2("foo");
+  assert(h2.size() == 2);
+  assert(h2[0] == 2);
+  assert(h2[1] == 1);
+}
+
+//]