gftool.fourier.tt2z_herm2

gftool.fourier.tt2z_herm2(tt, gf_t, z, herm2=<bound method Hermite2.from_taylor of <class 'gftool.hermpade.Hermite2'>>, quad='trapz', **kwds)[source]

Square Fourier-Padé transform of the real-time Green’s function gf_t.

Uses a square Hermite-Padé approximant for the transform. The function requires an equidistant tt.

Parameters:

tt(Nt) float np.ndarray: The equidistant points for which the Green’s function gf_t is given.
gf_t(…, Nt) complex np.ndarray: Green’s function at time points tt.
z(…, Nz) complex np.ndarray: Frequency points for which the Laplace transformed Green’s function should be evaluated.

Returns:

(…, Nz) complex np.ndarray: Laplace transformed Green’s function for complex frequencies z.

Other Parameters:

herm2{gftool.hermpade.Hermite2.from_taylor, gftool.hermpade.Hermite2.from_taylor_lstsq}: Hermite-Padé algorithm that is used.
quad{‘trapz’, ‘simps’}: Quadrature to discretize the Laplace integral.
**kwds: Optional key-word arguments passed to herm2.

Raises:

ValueError: If the time points tt are not equidistant.