gevp.hankel: GEVP method based on Hankel matrices.

In hadron: Analysis Framework for Monte Carlo Simulation Data in Physics

GEVP method based on Hankel matrices.

Description

Alternative method to determine energy levels from correlation matrices. A so-called Hankel matrix is generated from an input real numeric vector and a generalised eigenvalue problem is solved then.

Usage

gevp.hankel(cf, t0 = 1, deltat = 1, n, N, submatrix.size = 1,
  element.order = c(1, 2, 3, 4), Delta = 1)

Arguments

cf	Numeric vector (this will generally be the time slices of a correlation function).
t0	Integer. Initial time value of the GEVP, must be in between 0 and Time/2-2. Default is 1.
deltat	Integer. Time shift to be used to build the Hankel matrix
n	Integer. Size of the Hankel matrices to generate
N	Integer. Maximal time index in correlation function to be used in Hankel matrix
submatrix.size	Integer. Submatrix size to be used in build of Hankel matrices. Submatrix.size > 1 is experimental.
element.order	Integer vector. specifies how to fit the n linearly ordered single correlators into the correlator matrix for submatrix.size > 1. element.order=c(1,2,3,4) leads to a matrix matrix(cf[element.order], nrow=2). Matrix elements can occur multiple times, such as c(1,2,2,3) for the symmetric case, for example.
Delta	integer. Delta is the time shift used in the Hankel matrix.

Value

A complex vector of length n + n^2 which contains the eigenvalues in the first n elements and the eigenvectors in the remaining n^2 elements.

A vector of NAs of n + n^2 is returend in case the QR decomposition fails.

See Also

Other hankel: bootstrap.hankel_summed(), bootstrap.hankel(), gevp.hankel_summed(), hankel2cf(), hankel2effectivemass(), plot_hankel_spectrum()

hadron documentation built on Sept. 9, 2022, 5:06 p.m.