added statistics/errorbar

Author: MamoruSobue

gallery/statistics/CMakeLists.txt

@@ -1,8 +1,10 @@
 add_demo(hist hist.cpp)
+add_demo(errorbar errorbar.cpp)
 
 add_custom_target(statitics
-  DEPENDS hist
+  DEPENDS hist errorbar
   COMMAND hist
+  COMMAND errorbar
   COMMENT "running hist"
   WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/../images"
 )

gallery/statistics/errorbar.cpp

@@ -0,0 +1,31 @@
+// example from https://matplotlib.org/stable/gallery/statistics/errorbar.html
+
+#include <pybind11/embed.h>
+#include <pybind11/stl.h>
+
+#include <matplotlibcpp17/pyplot.h>
+
+#include <xtensor/xrandom.hpp>
+
+#include <random>
+
+namespace py = pybind11;
+using namespace py::literals;
+using namespace std;
+using namespace matplotlibcpp17;
+
+int main() {
+  py::scoped_interpreter guard{};
+  auto plt = pyplot::import();
+  auto x_ = xt::arange(0.1, 4.0, 0.5);
+  auto y_ = xt::exp(-x_);
+  vector<double> x(x_.begin(), x_.end()), y(y_.begin(), y_.end());
+
+  auto [fig, ax] = plt.subplots();
+  ax.errorbar(Args(x, y), Kwargs("xerr"_a = 0.2, "yerr"_a = 0.4));
+#if USE_GUI
+  plt.show();
+#else
+  plt.savefig(Args("erorrbar.png"));
+#endif
+}