more eigen examples

Cryoris · Cryoris · commit f872d23d4670 · 2019-06-10T17:02:15.000+02:00
diff --git a/Makefile b/Makefile
@@ -18,7 +18,7 @@ eigen_include = -I /usr/local/include/eigen3
 
 examples: minimal basic modern animation nonblock xkcd quiver bar surface subplot fill_inbetween fill update
 
-eigen: eigen_basic eigen_modern
+eigen: eigen_basic eigen_modern eigen_loglog
 
 minimal: examples/minimal.cpp matplotlibcpp.h
 	cd examples && g++ -DWITHOUT_NUMPY minimal.cpp ${includes} ${linkings} -o minimal ${definitions}
@@ -66,5 +66,9 @@ eigen_basic: examples/eigen/basic.cpp matplotlibcpp.h
 eigen_modern: examples/eigen/modern.cpp matplotlibcpp.h
 	cd examples/eigen && g++ modern.cpp ${includes} ${eigen_include} ${linkings} -o $@ ${definitions}
 
+eigen_loglog: examples/eigen/loglog.cpp matplotlibcpp.h
+	cd examples/eigen && g++ loglog.cpp ${includes} ${eigen_include} ${linkings} -o $@ ${definitions}
+
 clean:
 	rm -f examples/{minimal,basic,modern,animation,nonblock,xkcd,quiver,bar,surface,subplot,fill_inbetween,fill,update}
+	rm -f examples/eigen/{eigen_basic,eigen_modern,eigen_loglog}
diff --git a/examples/eigen/loglog.cpp b/examples/eigen/loglog.cpp
@@ -0,0 +1,37 @@
+#define _USE_MATH_DEFINES
+#include "../../matplotlibcpp.h"
+#include <Eigen/Dense>
+#include <cmath>
+#include <iostream>
+
+namespace plt = matplotlibcpp;
+
+int main() {
+  // Prepare data.
+  int n = 5000;
+  Eigen::VectorXd x(n), y(n), z(n), w = Eigen::VectorXd::Ones(n);
+  for (int i = 0; i < n; ++i) {
+    double value = (1.0 + i) / n;
+    x(i) = value;
+    y(i) = value * value;
+    z(i) = value * value * value;
+  }
+
+  // Plot line from given x and y data. Color is selected automatically.
+  plt::plot(x, w);
+
+  // Plot a red dashed line from given x and y data.
+  plt::plot(x, y, "r--");
+
+  // Plot a line whose name will show up as "log(x)" in the legend.
+  plt::plot(x, z, "g:", {{"label", "$x^3$"}});
+
+  // Add graph title
+  plt::title("Sample figure");
+
+  // Enable legend.
+  plt::legend();
+
+  // show figure
+  plt::show();
+}
diff --git a/examples/eigen/modern.cpp b/examples/eigen/modern.cpp
@@ -0,0 +1,29 @@
+#define _USE_MATH_DEFINES
+#include "../../matplotlibcpp.h"
+#include <Eigen/Dense>
+#include <cmath>
+
+namespace plt = matplotlibcpp;
+
+int main() {
+  // plot(y) - the x-coordinates are implicitly set to [0,1,...,n)
+  // plt::plot({1,2,3,4});
+
+  // Prepare data for parametric plot.
+  int n = 5000; // number of data points
+  Eigen::VectorXd x(n), y(n), z(n);
+  for (int i = 0; i < n; ++i) {
+    double t = 2 * M_PI * i / n;
+    x(i) = 16 * sin(t) * sin(t) * sin(t);
+    y(i) = 13 * cos(t) - 5 * cos(2 * t) - 2 * cos(3 * t) - cos(4 * t);
+    z(i) = 12.5 + abs(sin(x(i)));
+  }
+
+  // plot() takes an arbitrary number of (x,y,format)-triples.
+  // x must be iterable (that is, anything providing begin(x) and end(x)),
+  // y must either be callable (providing operator() const) or iterable.
+  plt::plot(x, z, "k-", x, y, "r-");
+
+  // show plots
+  plt::show();
+}
