Solver Accessors (Python)

Instances of the class Solver have a number of accessors, some of which are used as inputs to the calculation, some of which are used to retrieve the outputs of the calculation.

Input accessors

The input accessors are the following:

Member	Description	Type
G0	Bare Green’s function	BlockGfImFreq
K_tau	Retarded interaction kernel	GfImTime
Kprime_tau	Derivative of retarded interaction kernel	GfImTime

For calculations with static interactions, only G0 is needed.

Output accessors

The output accessors are the following (they are read-only):

Member	Description	Type
nn_tau	Density-density correlation function in imaginary time	GfImTime
nn_omega	Density-density correlation function on Matsubara frequencies	GfImFreq
G_tau	Imaginary-time Green’s function	BlockGfImTime
F_tau	Improved estimator in imaginary time	BlockGfImTime
G_legendre	Imaginary-time Green’s function	BlockGfLegendre
F_legendre	Improved estimator in imaginary time	BlockGfLegendre
G_omega	Matsubara Green’s function	BlockGfImFreq
F_omega	Improved estimator on Matsubara frequencies	BlockGfImFreq
Sigma_omega	Self-energy on Matsubara frequencies	BlockGfImFreq
nn	Density-density static correlations	numpy.array
hist	Histogram of perturbation order	numpy.array
state_hist	Histogram of perturbation order resolved by state	numpy.array

The data contained by the output accessors is meaningful only if the corresponding measurement (see options) has been turned on. Here is a list of the measures and the corresponding outputs:

Measure name	Measured observable	Byproduct
measure_gt	G_tau, F_tau
measure_gl	G_legendre, F_legendre
measure_gw	G_omega, F_omega	Sigma_omega
measure_nn	nn
measure_nnt	nn_tau
measure_nnw	nn_omega
measure_hist	hist
measure_statehist	state_hist

Hence, if you e.g. switch on measure_gw, you should not attempt to access G_tau : the corresponding container will be empty.