Map

Overview

class

cntr::herm_matrix_timestep_view<T>

The purpose of this class is to create a map to a pre-existing object of type cntr::herm_matrix or cntr::herm_matrix_timestep. One can then use this class without making a physical copy of the original data. The structure is inherited from the existing object. The usage of this class is mainly reserved for active developers as it is employed to enhance a performance of low-lying routines and MPI communications. It is characterized by the following parameters:

  • T (template parameter): Precision, usually set to double; we use the definition

    #define GREEN_TSTP_VIEW cntr::herm_matrix_timestep_view<double>

  • tstp (integer): The timestep variable, tstp>=-1.

  • ntau (integer): number of discretization points on the imaginary time axis, ntau>=0

  • size1 (integer): orbital dimension. Each element \(C(t,t')\) is a square matrix of dimension size1 \(\times\) size1.

  • sig (FERMION or BOSON).

Constructors

herm_matrix_timestep_view<T>()

Default constructor, does not allocate memory and sets nt=-2.

herm_matrix_timestep_view<T>(int tstp,int ntau,int size1, int size2, int sig)

Creates a map with all entries to 0. It requires tstp>=-1, ntau>0, size1>0, size2>0, and sig=FERMION or sig=BOSON.

herm_matrix_timestep_view(int tstp, herm_matrix<T> &g)

Creates a map to the predefined herm_matrix object g at a given time tstp. Similar constructor exists for herm_matrix_timestep.

Accessing and manipulation

In general, all functions described for herm_matrix_timestep argument in Overview can be replaced by a herm_matrix_timestep_view argument following the same syntax.