jacobian

commit 879128a1e0e33613f443252ce125f9681aa70e46
parent 4d9a93e3a40b568021b0c671ca2fbc5f300616ea
Author: David Freifeld <freifeld.david@gmail.com>
Date:   Tue, 30 Jun 2020 21:00:09 -0700

Beginnings of Strassen tests

Diffstat:
A
tests/strassen.cpp
 | 
25
+++++++++++++++++++++++++

1 file changed, 25 insertions(+), 0 deletions(-)
diff --git a/tests/strassen.cpp b/tests/strassen.cpp
@@ -0,0 +1,25 @@
+//
+// strassen.cpp
+// Experimental benchmarking of Strassen's Algorithm vs plain Eigen matrix multipy
+//
+// While naive multiplication is O(n^3), Strassen's Algorithm for matrix multiply is O(n^2.8074)
+// which means significant differences will begin to manifest for large matrices. All faster algorithms are galactic.
+//
+
+#include <Eigen/Dense>
+
+// Not extensible, just initial test.
+Eigen::MatrixXd strassen_mul(Eigen::MatrixXd a, Eigen::MatrixXd b)
+{
+  block_len = a.rows()/4;
+}
+
+Eigen::MatrixXd a = Eigen::MatrixXd::Random(5000, 5000);
+Eigen::MatrixXd b = Eigen::MatrixXd::Random(5000, 5000);
+
+auto eigen_begin = std::chrono::high_resolution_clock::now();
+Eigen::MatrixXd product = a * b;
+auto eigen_end = std::chrono::high_resolution_clock::now();
+
+auto strassen_begin = std::chrono::high_resolution_clock::now();
+auto strassen_end = std::chrono::high_resolution_clock::now();