flops file

lab03/jacobi_bench2_changed_flops.cpp

@@ -0,0 +1,89 @@
+#include "matrix.h"
+#include <iostream>
+#include <fstream>
+#include <benchmark/benchmark.h>
+
+Matrix jacobi(const Matrix& init, double eps, int maxNumIter) {
+  Matrix phi(init);
+  Matrix tmp(init.dim());
+
+  const int n = phi.dim1();
+  const int m = phi.dim2();
+
+  for (int i = 0; i < n; ++i) {
+    tmp(i, 0) = phi(i, 0);
+    tmp(i, m - 1) = phi(i, m - 1);
+  }
+  for (int j = 0; j < m; ++j) {
+    tmp(0, j) = phi(0, j);
+    tmp(n - 1, j) = phi(n - 1, j);
+  }
+
+  double dist = 1e10;
+  int nIter = 0;
+  while (dist > eps && nIter < maxNumIter) {
+    dist = 0;
+    for (int i = 1; i < n - 1; ++i) {
+      for (int j = 1; j < m - 1; ++j) {
+        tmp(i, j) = .25 * (phi(i + 1, j) + phi(i - 1, j) + phi(i, j + 1) +
+                                 phi(i, j - 1));
+        dist = std::max(dist, std::abs(tmp(i, j) - phi(i, j)));
+      }
+    }
+
+    std::swap(tmp, phi);
+
+
+    // std::cout << l2phi << ", " << l2tmp << ", " << dist << std::endl;
+
+    nIter++;
+  }
+
+  return phi;
+}
+
+Matrix initialCondition(int n) {
+  Matrix m(n, n);
+  for (int i = 0; i < n; ++i) {
+    const double x = 1. * i / n;
+
+    for (int j = 0; j < n; ++j) {
+      const double y = 1. * j / n;
+
+      // The lower left corner is hot
+      m(i, j) += exp(-0.5 * (x * x + y * y) * 10) * exp(-100 * x * y);
+
+      // The right side is cold
+      m(i, j) += -1.0 * exp(-20 * (1 - y));
+    }
+  }
+  return m;
+}
+
+void storeMatrix(const Matrix& m, const std::string& filename) {
+  std::ofstream fout(filename);
+  fout << m << std::endl;
+}
+
+// int main() {
+//   const Matrix init = initialCondition(200);
+//   storeMatrix(init, "init.asc");
+//   Matrix phi = jacobi(init, 1e-5, 100000);
+//   storeMatrix(phi, "solution.asc");
+// }
+
+void benchmarkJacobi(benchmark::State& state) {
+  int n = state.range(0);
+  const Matrix init = initialCondition(n);
+  Matrix phi;
+
+  for (auto _ : state) {
+    phi = jacobi(init, 1e-5, 100000);  // Reduce max iterations for quicker tests
+  }
+
+  state.counters["Size"] = n; // Optional: include n in the output
+}
+
+BENCHMARK(benchmarkJacobi)->Unit(benchmark::kMillisecond)->RangeMultiplier(2)->DenseRange(100, 2000, 20);
+BENCHMARK_MAIN();
+