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// 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)
//[ guide_fill_profile
#include <boost/format.hpp>
#include <boost/histogram.hpp>
#include <cassert>
#include <iostream>
#include <sstream>
#include <tuple>
int main() {
using namespace boost::histogram;
// make a profile, it computes the mean of the samples in each histogram cell
auto h = make_profile(axis::integer<>(0, 3));
// mean is computed from the values marked with the sample() helper function
h(0, sample(1)); // sample goes to cell 0
h(0, sample(2)); // sample goes to cell 0
h(1, sample(3)); // sample goes to cell 1
h(sample(4), 1); // sample goes to cell 1; sample can be first or last argument
// fills from tuples are also supported, 5 and 6 go to cell 2
auto a = std::make_tuple(2, sample(5));
auto b = std::make_tuple(sample(6), 2);
h(a);
h(b);
// builtin accumulators have methods to access their state
std::ostringstream os;
for (auto&& x : indexed(h)) {
// use `.` to access methods of accessor, like `index()`
// use `->` to access methods of accumulator
const auto i = x.index();
const auto n = x->count(); // how many samples are in this bin
const auto vl = x->value(); // mean value
const auto vr = x->variance(); // estimated variance of the mean value
os << boost::format("index %i count %i value %.1f variance %.1f\n") % i % n % vl % vr;
}
std::cout << os.str() << std::flush;
assert(os.str() == "index 0 count 2 value 1.5 variance 0.5\n"
"index 1 count 2 value 3.5 variance 0.5\n"
"index 2 count 2 value 5.5 variance 0.5\n");
}
//]
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