| // g++ -O3 -DNDEBUG benchmarkX.cpp -o benchmarkX && time ./benchmarkX | 
 |  | 
 | #include <Eigen/Core> | 
 |  | 
 | using namespace std; | 
 | using namespace Eigen; | 
 |  | 
 | #ifndef VECTYPE | 
 | #define VECTYPE VectorXLd | 
 | #endif | 
 |  | 
 | #ifndef VECSIZE | 
 | #define VECSIZE 1000000 | 
 | #endif | 
 |  | 
 | #ifndef REPEAT | 
 | #define REPEAT 1000 | 
 | #endif | 
 |  | 
 | int main(int argc, char *argv[]) | 
 | { | 
 | 	VECTYPE I = VECTYPE::Ones(VECSIZE); | 
 | 	VECTYPE m(VECSIZE,1); | 
 | 	for(int i = 0; i < VECSIZE; i++) | 
 | 	{ | 
 | 		m[i] = 0.1 * i/VECSIZE; | 
 | 	} | 
 | 	for(int a = 0; a < REPEAT; a++) | 
 | 	{ | 
 | 		m = VECTYPE::Ones(VECSIZE) + 0.00005 * (m.cwise().square() + m/4); | 
 | 	} | 
 | 	cout << m[0] << endl; | 
 | 	return 0; | 
 | } |