remove gf_struct_flatten function and replace with triqs version

doc/ChangeLog.md

@@ -23,11 +23,11 @@ DFTTools Version 3.1.0 is a release that
 * bugfix: This fix makes the function find_rot_mat() safer to use in case there are errors in finding the correct mapping. The converter will now abort if the agreement in mapping is below a user-definable threshold.
 
 ### Change in gf_struct
-* In line with TRIQS 3.1.x, the form of the Green's function's structure (`gf_struct`) has been modified
+* In line with TRIQS 3.1.x, the form of the Green's function's structure (`gf_struct`) has been modified (see [triqs changelog](https://triqs.github.io/triqs/latest/ChangeLog.html#change-in-gf-struct-objects) for more information)
 * Instead of `gf_struct = [("up", [0, 1]), ("down", [0, 1])]`, the new convention uses `gf_struct = [("up", 2), ("down", 2)]`
 * This modifies the form of `gf_struct_solver` (and `sumk`) in `block_structure` and `SumkDFT` as well.
 * Backwards-compatibility with old, stored `block_structure` objects is given, however a warning is issued.
-* A helper-function `block_structure.gf_struct_flatten(...)` is provided to manually bring `gf_struct`s to the new form.
+* A helper-function `triqs.gf.block_gf.fix_gf_struct_type(gf_struct_old)` is provided in triqs to manually bring `gf_struct`s to the new form.
 
 ### Documentation
 * change to read the docs sphinx theme

doc/tutorials/images_scripts/nio.py

@@ -6,7 +6,6 @@ from triqs.gf import *
 import sys, triqs.version as triqs_version
 from triqs_dft_tools.sumk_dft import *
 from triqs_dft_tools.sumk_dft_tools import *
-from triqs_dft_tools.block_structure import gf_struct_flatten
 from triqs.operators.util.hamiltonians import *
 from triqs.operators.util.U_matrix import *
 from triqs_cthyb import *
@@ -41,7 +40,7 @@ spin_names = ['up','down']
 orb_names = [i for i in range(0,n_orb)]
 
 #gf_struct = set_operator_structure(spin_names, orb_names, orb_hyb)
-gf_struct = gf_struct_flatten(SK.gf_struct_solver[0])
+gf_struct = SK.gf_struct_solver_list[0]
 mpi.report('Sumk to Solver: %s'%SK.sumk_to_solver)
 mpi.report('GF struct sumk: %s'%SK.gf_struct_sumk)
 mpi.report('GF struct solver: %s'%SK.gf_struct_solver)

doc/tutorials/images_scripts/nio_csc.py

@@ -6,7 +6,6 @@ from triqs.gf import *
 import sys, triqs.version as triqs_version
 from triqs_dft_tools.sumk_dft import *
 from triqs_dft_tools.sumk_dft_tools import *
-from triqs_dft_tools.block_structure import gf_struct_flatten
 from triqs.operators.util.hamiltonians import *
 from triqs.operators.util.U_matrix import *
 from triqs_cthyb import *
@@ -48,7 +47,7 @@ def dmft_cycle():
     orb_names = [i for i in range(0,n_orb)]
 
     #gf_struct = set_operator_structure(spin_names, orb_names, orb_hyb)
-    gf_struct = SK.gf_struct_solver[0]
+    gf_struct = SK.gf_struct_solver_list[0]
     mpi.report('Sumk to Solver: %s'%SK.sumk_to_solver)
     mpi.report('GF struct sumk: %s'%SK.gf_struct_sumk)
     mpi.report('GF struct solver: %s'%SK.gf_struct_solver)

python/triqs_dft_tools/block_structure.py

@@ -1190,45 +1190,5 @@ class BlockStructure(object):
         s += str(self.transformation)
         return s
 
-def gf_struct_flatten(gf_struct):
-    '''
-    flattens gf_struct objecti
-
-    input gf_struct can looks like this:
-
-    [('up', [0, 1, 2]), ('down', [0, 1, 2])]
-
-    and will be returned as
-
-    [('up', 3), ('down', 3)]
-
-    Same for dict but replacing the values. This is for compatibility with the upcoming triqs releases.
-
-    Parameters
-    ----------
-    gf_struct: list of tuple or dict representing the Gf structure
-    __Returns:__
-    gf_struct_flat: flattens the values of the dict or the tuple representing the Gf indices by replacing them with the len of the list of indices
-
-    '''
-
-    if isinstance(gf_struct, list):
-        # create a copy of the original list
-        gf_struct_flat = gf_struct.copy()
-        for idx, block in enumerate(gf_struct_flat):
-            # exchange list of indices with length of list
-            gf_struct_flat[idx] = (block[0], len(block[1]))
-    elif isinstance(gf_struct, dict):
-        # create a copy of the original dict
-        gf_struct_flat = dict(gf_struct)
-        for key, value in gf_struct_flat.items():
-            # exchange list of indices with length of list
-            gf_struct_flat[key] = len(value)
-    else:
-        raise Exception('gf_struct input needs to be list or dict')
-
-
-    return gf_struct_flat
-
 from h5.formats import register_class
 register_class(BlockStructure)

test/python/blockstructure.py

@@ -3,7 +3,7 @@ from triqs.utility.h5diff import h5diff, compare, failures
 from triqs.gf import *
 from triqs.utility.comparison_tests import assert_block_gfs_are_close
 from scipy.linalg import expm
-from triqs_dft_tools.block_structure import BlockStructure, gf_struct_flatten
+from triqs_dft_tools.block_structure import BlockStructure
 import numpy as np