mirror of
https://github.com/boostorg/histogram.git
synced 2025-05-11 05:07:58 +00:00
52 lines
1.8 KiB
C++
52 lines
1.8 KiB
C++
//[ getting_started_listing_02
|
|
|
|
#include <boost/histogram.hpp>
|
|
#include <boost/random/mersenne_twister.hpp>
|
|
#include <boost/random/normal_distribution.hpp>
|
|
#include <cstdlib>
|
|
#include <string>
|
|
|
|
namespace br = boost::random;
|
|
namespace bh = boost::histogram;
|
|
|
|
int main() {
|
|
/*
|
|
create a dynamic histogram with the factory `make_dynamic_histogram`
|
|
- axis can be passed directly just like for `make_static_histogram`
|
|
- in addition, the factory also accepts iterators over a sequence of
|
|
axis::any, the polymorphic type that can hold concrete axis types
|
|
*/
|
|
std::vector<bh::axis::any_builtin> axes;
|
|
axes.emplace_back(bh::axis::category<std::string>({"red", "blue"}));
|
|
axes.emplace_back(bh::axis::regular<>(5, -5, 5, "x"));
|
|
axes.emplace_back(bh::axis::regular<>(5, -5, 5, "y"));
|
|
auto h = bh::make_dynamic_histogram(axes.begin(), axes.end());
|
|
|
|
// fill histogram with random numbers
|
|
br::mt19937 gen;
|
|
br::normal_distribution<> norm;
|
|
for (int i = 0; i < 1000; ++i)
|
|
h(i % 2 ? "red" : "blue", norm(gen), norm(gen));
|
|
|
|
/*
|
|
print dynamic histogram by iterating over bins
|
|
- for most axis types, the for loop looks just like for a static
|
|
histogram, except that we can pass runtime numbers, too
|
|
- if the [bin type] of the axis is not convertible to a
|
|
double interval, one needs to cast axis::any before looping;
|
|
this is here the case for the category axis
|
|
*/
|
|
using cas = bh::axis::category<std::string>;
|
|
for (auto cbin : bh::axis::cast<cas>(h.axis(0))) {
|
|
std::printf("%s\n", cbin.value().c_str());
|
|
for (auto ybin : h.axis(2)) { // rows
|
|
for (auto xbin : h.axis(1)) { // columns
|
|
std::printf("%3.0f ", h.at(cbin, xbin, ybin).value());
|
|
}
|
|
std::printf("\n");
|
|
}
|
|
}
|
|
}
|
|
|
|
//]
|