Memory, time and technique aspects of density matrix renormalization groupmethod

We present the memory size, computational time, and technique aspects of de nsity matrix renormalization group (DMRG) algorithm. We show how to estimat e the memory size and computational time before starting a large scale DMRG calculation. We propose an implementation of the Hamiltonian wavefunction multiplication and a wavefunction initialization in DMRG with block matrix data structure. One-dimensional Heisenberg model is used to illustrate our study.