Squashed 'third_party/matplotlib-cpp/' content from commit f994996

Change-Id: I2124d6ed85284acca42fc0e90f489f422e6e440a
git-subtree-dir: third_party/matplotlib-cpp
git-subtree-split: f994996e0724f30612154a26cbdc660ad9c51907
diff --git a/examples/xkcd.cpp b/examples/xkcd.cpp
new file mode 100644
index 0000000..9bf6454
--- /dev/null
+++ b/examples/xkcd.cpp
@@ -0,0 +1,21 @@
+#include "../matplotlibcpp.h"
+#include <vector>
+#include <cmath>
+
+namespace plt = matplotlibcpp;
+
+int main() {
+    std::vector<double> t(1000);
+    std::vector<double> x(t.size());
+
+    for(size_t i = 0; i < t.size(); i++) {
+        t[i] = i / 100.0;
+        x[i] = sin(2.0 * M_PI * 1.0 * t[i]);
+    }
+
+    plt::xkcd();
+    plt::plot(t, x);
+    plt::title("AN ORDINARY SIN WAVE");
+    plt::show();
+}
+