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// Copyright 2015-2018 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_custom_minimal_axis
#include <boost/histogram.hpp>
#include <cassert>
int main() {
using namespace boost::histogram;
// stateless axis which returns 1 if the input is even and 0 otherwise
struct even_odd_axis {
axis::index_type index(int x) const { return x % 2; }
axis::index_type size() const { return 2; }
};
// threshold axis which returns 1 if the input is above threshold
struct threshold_axis {
threshold_axis(double x) : thr(x) {}
axis::index_type index(double x) const { return x >= thr; }
axis::index_type size() const { return 2; }
double thr;
};
auto h = make_histogram(even_odd_axis(), threshold_axis(3.0));
h(0, 2.0);
h(1, 4.0);
h(2, 4.0);
assert(h.at(0, 0) == 1); // even, below threshold
assert(h.at(0, 1) == 1); // even, above threshold
assert(h.at(1, 0) == 0); // odd, below threshold
assert(h.at(1, 1) == 1); // odd, above threshold
}
//]
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