1 // Copyright 2019 Hans Dembinski
2 //
3 // Distributed under the Boost Software License, Version 1.0.
4 // (See accompanying file LICENSE_1_0.txt
5 // or copy at http://www.boost.org/LICENSE_1_0.txt)
6
7 //[ guide_axis_circular
8
9 #include <boost/histogram/axis.hpp>
10 #include <limits>
11
main()12 int main() {
13 using namespace boost::histogram;
14
15 // make a circular regular axis ... [0, 180), [180, 360), [0, 180) ....
16 using opts = decltype(axis::option::overflow | axis::option::circular);
17 auto r = axis::regular<double, use_default, use_default, opts>{2, 0., 360.};
18 assert(r.index(-180) == 1);
19 assert(r.index(0) == 0);
20 assert(r.index(180) == 1);
21 assert(r.index(360) == 0);
22 assert(r.index(540) == 1);
23 assert(r.index(720) == 0);
24 // special values are mapped to the overflow bin index
25 assert(r.index(std::numeric_limits<double>::infinity()) == 2);
26 assert(r.index(-std::numeric_limits<double>::infinity()) == 2);
27 assert(r.index(std::numeric_limits<double>::quiet_NaN()) == 2);
28
29 // since the regular axis is the most common circular axis, there exists an alias
30 auto c = axis::circular<>{2, 0., 360.};
31 assert(r == c);
32
33 // make a circular integer axis
34 auto i = axis::integer<int, use_default, axis::option::circular_t>{1, 4};
35 assert(i.index(0) == 2);
36 assert(i.index(1) == 0);
37 assert(i.index(2) == 1);
38 assert(i.index(3) == 2);
39 assert(i.index(4) == 0);
40 assert(i.index(5) == 1);
41 }
42
43 //]
44