triqs.gfs.block2_gf.Block2Gf

class triqs.gfs.block2_gf.Block2Gf(name_list1, name_list2, block_list, **kwargs)[source]

Bases: object

Two-index block-diagonal Green’s function.

A Block2Gf is a rectangular, named collection of Gf blocks indexed by a pair (bn1, bn2) drawn from two — possibly distinct — sets of block names. It is the natural container for two-particle / four-leg quantities such as susceptibilities and vertex functions. Block access uses tuple indexing (g['up', 'dn']). Iteration yields ((bn1, bn2), block) pairs in row-major order.

Parameters:

name_list1sequence of hashable: Block names of the first index.
name_list2sequence of hashable: Block names of the second index.
block_listlist of lists of Gf, or callable: Either a 2D nested list of shape (len(name_list1), len(name_list2)) of Gf blocks, or a callable f(bn1, bn2) -> Gf invoked for every name pair.
make_copiesbool, optional: If True, store deep copies of the blocks; otherwise store the references. Default False.
namestr, optional: Plot label. Default ''.

Attributes

`indices`	Iterate over `(bn1, bn2)` pairs in row-major order.
`indices1`	Iterate over the first-index block names.
`indices2`	Iterate over the second-index block names.
`all_indices`	Iterate over flat indices `(bn1, bn2, i, j, ...)` for every target-space entry of every block.
`n_blocks`	Total number of blocks.
`real`	Block-wise view of the real part of every block.
`imag`	Block-wise view of the imaginary part of every block.

name

(str) Plot label; also used as a prefix for the individual block names.

Methods

`copy`(*args)	Return an independent deep copy of `self` (every block is copied).
`copy_from`(G2)	Copy the data of `G2` into `self` block by block.
`copy_selected_blocks`(selected_blocks1, ...)	Return a new `Block2Gf` containing deep copies of the named blocks.
`view_selected_blocks`(selected_blocks1, ...)	Return a new `Block2Gf` containing views of the named blocks.
`zero`()	Set every block's data to zero, in place.

Notes

All blocks must be of the same Python type (e.g. all Gf).
The << operator broadcasts initializers to every block; see __lshift__().

Examples

Construct a 2x2 block susceptibility on a bosonic Matsubara mesh and iterate over the blocks:

>>> from triqs.gfs import Block2Gf, Gf
>>> from triqs.mesh import MeshImFreq
>>> mesh = MeshImFreq(beta=10.0, statistic='Boson', n_iw=64)
>>> chi = Block2Gf(['up', 'dn'], ['up', 'dn'],
...                lambda b1, b2: Gf(mesh=mesh, target_shape=[1, 1]),
...                name='chi')
>>> for (bn1, bn2), g in chi:
...     print(bn1, bn2, g.target_shape)