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 // clang-format off
8
9 //[ guide_axis_growing
10
11 #include <boost/histogram.hpp>
12 #include <cassert>
13
14 #include <iostream>
15
main()16 int main() {
17 using namespace boost::histogram;
18
19 // make a growing regular axis
20 // - it grows new bins with its constant bin width until the value is covered
21 auto h1 = make_histogram(axis::regular<double,
22 use_default,
23 use_default,
24 axis::option::growth_t>{2, 0., 1.});
25 // nothing special happens here
26 h1(0.1);
27 h1(0.9);
28 // state: [0, 0.5): 1, [0.5, 1.0): 1
29 assert(h1.axis().size() == 2);
30 assert(h1.axis().bin(0).lower() == 0.0);
31 assert(h1.axis().bin(1).upper() == 1.0);
32
33 // value below range: axis grows new bins until value is in range
34 h1(-0.3);
35 // state: [-0.5, 0.0): 1, [0, 0.5): 1, [0.5, 1.0): 1
36 assert(h1.axis().size() == 3);
37 assert(h1.axis().bin(0).lower() == -0.5);
38 assert(h1.axis().bin(2).upper() == 1.0);
39
40 h1(1.9);
41 // 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
42 assert(h1.axis().size() == 5);
43 assert(h1.axis().bin(0).lower() == -0.5);
44 assert(h1.axis().bin(4).upper() == 2.0);
45
46 // make a growing category axis (here strings)
47 // - empty axis is allowed: very useful if categories are not known at the beginning
48 auto h2 = make_histogram(axis::category<std::string,
49 use_default,
50 axis::option::growth_t>());
51 assert(h2.size() == 0); // histogram is empty
52 h2("foo"); // new bin foo, index 0
53 assert(h2.size() == 1);
54 h2("bar"); // new bin bar, index 1
55 assert(h2.size() == 2);
56 h2("foo");
57 assert(h2.size() == 2);
58 assert(h2[0] == 2);
59 assert(h2[1] == 1);
60 }
61
62 //]
63