lbfgspp 0.3.0 (new formula)

Formula/l/lbfgspp.rb

@@ -0,0 +1,64 @@
+class Lbfgspp < Formula
+  desc "Header-only C++ library for L-BFGS and L-BFGS-B algorithms"
+  homepage "https://lbfgspp.statr.me/"
+  url "https://github.com/yixuan/LBFGSpp/archive/refs/tags/v0.3.0.tar.gz"
+  sha256 "490720b9d5acce6459cb0336ca3ae0ffc48677225f0ebfb35c9bef6baefdfc6a"
+  license "MIT"
+  head "https://github.com/yixuan/LBFGSpp.git", branch: "master"
+
+  depends_on "cmake" => :build
+  depends_on "eigen"
+
+  def install
+    system "cmake", "-S", ".", "-B", "build", *std_cmake_args
+    system "cmake", "--build", "build"
+    system "cmake", "--install", "build"
+  end
+
+  test do
+    (testpath/"test.cpp").write <<~CPP
+      #include <Eigen/Core>
+      #include <iostream>
+      #include <LBFGS.h>
+
+      using Eigen::VectorXd;
+      using namespace LBFGSpp;
+
+      class Rosenbrock {
+      private:
+          int n;
+      public:
+          Rosenbrock(int n_) : n(n_) {}
+          double operator()(const VectorXd& x, VectorXd& grad) {
+              double fx = 0.0;
+              for(int i = 0; i < n; i += 2) {
+                  double t1 = 1.0 - x[i];
+                  double t2 = 10 * (x[i + 1] - x[i] * x[i]);
+                  grad[i + 1] = 20 * t2;
+                  grad[i]     = -2.0 * (x[i] * grad[i + 1] + t1);
+                  fx += t1 * t1 + t2 * t2;
+              }
+              return fx;
+          }
+      };
+
+      int main() {
+          const int n = 10;
+          LBFGSParam<double> param;
+          param.epsilon = 1e-6;
+          param.max_iterations = 100;
+          LBFGSSolver<double> solver(param);
+          Rosenbrock fun(n);
+          VectorXd x = VectorXd::Zero(n);
+          double fx;
+          solver.minimize(fun, x, fx);
+          std::cout << x.transpose() << std::endl;
+          return 0;
+      }
+    CPP
+    system ENV.cxx, testpath/"test.cpp", "-std=c++11",
+           "-I#{include}", "-I#{Formula["eigen"].opt_include}/eigen3",
+           "-o", "test"
+    assert_equal "1 1 1 1 1 1 1 1 1 1", shell_output(testpath/"test").chomp
+  end
+end