jacobian

commit 594bb23b98d8c94b7e4892abfb813e505185cd88
parent b20b12d27fcbd4be91f29697107e10a4e36fcda9
Author: David Freifeld <freifeld.david@gmail.com>
Date:   Thu, 30 Jul 2020 16:26:17 -0700

Experiments show cwise functions are faster

Diffstat:
A
tests/simd.cpp
 | 
21
+++++++++++++++++++++

1 file changed, 21 insertions(+), 0 deletions(-)
diff --git a/tests/simd.cpp b/tests/simd.cpp
@@ -0,0 +1,21 @@
+#include <Eigen/Dense>
+#include <ctime>
+#include <iostream>
+#include <cmath>
+
+int main()
+{
+  Eigen::MatrixXf a = Eigen::MatrixXf::Random(1000, 1000);
+
+  auto simd_start = std::chrono::high_resolution_clock::now();
+  a.array().exp().matrix();
+  auto simd_end = std::chrono::high_resolution_clock::now();
+  auto start = std::chrono::high_resolution_clock::now();
+  for (int i = 0; i < a.rows(); i++) {
+    for (int j = 0; j < a.cols(); j++) {
+      a(i,j) = exp(a(i,j));
+    }
+  }
+  auto end = std::chrono::high_resolution_clock::now();
+  std::cout << "SIMD: " << std::chrono::duration_cast<std::chrono::nanoseconds>(simd_end - simd_start).count() << " NORMAL: " << std::chrono::duration_cast<std::chrono::nanoseconds>(end - start).count() << "\n";
+}