void blas_gemm(const MatrixXcd& a, const MatrixXcd& b, MatrixXcd& c)
{
int M = c.rows(); int N = c.cols(); int K = a.cols();
int lda = a.rows(); int ldb = b.rows(); int ldc = c.rows();
zgemm_(¬rans,¬rans,&M,&N,&K,(double*)&cdone,
const_cast<double*>((const double*)a.data()),&lda,
const_cast<double*>((const double*)b.data()),&ldb,(double*)&cdone,
(double*)c.data(),&ldc);
}
/*!
Applies the inverse.
*/
void apply_Inverse(MatrixXcd& matrix, int mStart) {
int n = matrix.cols();
int start = nStart-mStart;
if (isLeaf == true) {
matrix.block(start, 0, nSize, n) = Kinverse.solve(matrix.block(start, 0, nSize, n));
}
else if (isLeaf == false) {
// Computes temp = Vinverse*matrix
MatrixXcd temp(nRank[0]+nRank[1], n);
temp.block(0, 0, nRank[0] , n) = Vinverse[1]*matrix.block(start+child[0]->nSize, 0 , child[1]->nSize, n);
temp.block(nRank[0], 0, nRank[1] , n) = Vinverse[0]*matrix.block(start, 0 , child[0]->nSize, n);
// Computes tempSolve = Kinverse\temp
MatrixXcd tempSolve = Kinverse.solve(temp);
// Computes matrix = matrix-Uinverse*tempSolve
matrix.block(start, 0, child[0]->nSize, n) = matrix.block(start, 0, child[0]->nSize, n) - Uinverse[0]*tempSolve.block(0, 0, nRank[0], n);
matrix.block(start + child[0]->nSize, 0, child[1]->nSize, n) = matrix.block(start + child[0]->nSize, 0, child[1]->nSize, n) - Uinverse[1]*tempSolve.block(nRank[0], 0, nRank[1], n);
}
};
Measurement::Measurement(MatrixXcd observable)
{
ComplexEigenSolver<MatrixXcd> solver(observable);
MatrixXcd vectors = solver.eigenvectors();
for (int i = 0; i < vectors.cols(); ++i)
addOperator(vectors.col(i) * vectors.col(i).transpose(), i_to_string(i));
_checkOperatorsAreValid();
}
/*!
Matrix matrix product.
*/
void matrix_Matrix_Product(MatrixXcd& x, MatrixXcd& b) {
int n = x.cols();
if (isLeaf == true) {
b.block(nStart, 0, nSize, n) = b.block(nStart, 0, nSize, n) + K*x.block(nStart, 0, nSize, n);
}
else if (isLeaf == false) {
int n0 = child[0]->nStart;
int n1 = child[1]->nStart;
int m0 = child[0]->nSize;
int m1 = child[1]->nSize;
b.block(n0, 0, m0, n) = b.block(n0, 0, m0, n) + U[0]*(V[1]*x.block(n1, 0, m1, n));
b.block(n1, 0, m1, n) = b.block(n1, 0, m1, n) + U[1]*(V[0]*x.block(n0, 0, m0, n));
}
};