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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)
// clang-format off
//[ getting_started_listing_02
#include <boost/format.hpp>
#include <boost/histogram.hpp>
#include <cassert>
#include <iostream>
#include <sstream>
#include <string>
int main() {
using namespace boost::histogram;
/*
Create a histogram which can be configured dynamically at run-time. The axis
configuration is first collected in a vector of axis::variant type, which
can hold different axis types (those in its template argument list). Here,
we use a variant that can store a regular and a category axis.
*/
using reg = axis::regular<>;
using cat = axis::category<std::string>;
using variant = axis::variant<axis::regular<>, axis::category<std::string>>;
std::vector<variant> axes;
axes.emplace_back(cat({"red", "blue"}));
axes.emplace_back(reg(3, 0.0, 1.0, "x"));
axes.emplace_back(reg(3, 0.0, 1.0, "y"));
// passing an iterator range also works here
auto h = make_histogram(std::move(axes));
// fill histogram with data, usually this happens in a loop
h("red", 0.1, 0.2);
h("blue", 0.7, 0.3);
h("red", 0.3, 0.7);
h("red", 0.7, 0.7);
/*
Print histogram by iterating over bins.
Since the [bin type] of the category axis cannot be converted into a double,
it cannot be handled by the polymorphic interface of axis::variant. We use
axis::get to "cast" the variant type to the actual category type.
*/
// get reference to category axis, performs a run-time checked static cast
const auto& cat_axis = axis::get<cat>(h.axis(0));
std::ostringstream os;
for (auto&& x : indexed(h)) {
os << boost::format("(%i, %i, %i) %4s [%3.1f, %3.1f) [%3.1f, %3.1f) %3.0f\n")
% x.index(0) % x.index(1) % x.index(2)
% cat_axis.bin(x.index(0))
% x.bin(1).lower() % x.bin(1).upper()
% x.bin(2).lower() % x.bin(2).upper()
% *x;
}
std::cout << os.str() << std::flush;
assert(os.str() == "(0, 0, 0) red [0.0, 0.3) [0.0, 0.3) 1\n"
"(1, 0, 0) blue [0.0, 0.3) [0.0, 0.3) 0\n"
"(0, 1, 0) red [0.3, 0.7) [0.0, 0.3) 0\n"
"(1, 1, 0) blue [0.3, 0.7) [0.0, 0.3) 0\n"
"(0, 2, 0) red [0.7, 1.0) [0.0, 0.3) 0\n"
"(1, 2, 0) blue [0.7, 1.0) [0.0, 0.3) 1\n"
"(0, 0, 1) red [0.0, 0.3) [0.3, 0.7) 0\n"
"(1, 0, 1) blue [0.0, 0.3) [0.3, 0.7) 0\n"
"(0, 1, 1) red [0.3, 0.7) [0.3, 0.7) 0\n"
"(1, 1, 1) blue [0.3, 0.7) [0.3, 0.7) 0\n"
"(0, 2, 1) red [0.7, 1.0) [0.3, 0.7) 0\n"
"(1, 2, 1) blue [0.7, 1.0) [0.3, 0.7) 0\n"
"(0, 0, 2) red [0.0, 0.3) [0.7, 1.0) 1\n"
"(1, 0, 2) blue [0.0, 0.3) [0.7, 1.0) 0\n"
"(0, 1, 2) red [0.3, 0.7) [0.7, 1.0) 0\n"
"(1, 1, 2) blue [0.3, 0.7) [0.7, 1.0) 0\n"
"(0, 2, 2) red [0.7, 1.0) [0.7, 1.0) 1\n"
"(1, 2, 2) blue [0.7, 1.0) [0.7, 1.0) 0\n");
}
//]
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