rust: Pass ev/back method

src/eko/evolution_operator/__init__.py.patch

@@ -1,5 +1,5 @@
 diff --git a/src/eko/evolution_operator/__init__.py b/src/eko/evolution_operator/__init__.py
-index fe07ade9..0f58c9e5 100644
+index fe07ade9..20c4539d 100644
 --- a/src/eko/evolution_operator/__init__.py
 +++ b/src/eko/evolution_operator/__init__.py
 @@ -3,16 +3,16 @@ r"""Contains the central operator classes.
@@ -588,7 +588,7 @@ index fe07ade9..0f58c9e5 100644
      def initialize_op_members(self):
          """Init all operators with the identity or zeros."""
          eye = OpMember(
-@@ -858,10 +317,13 @@ class Operator(sv.ScaleVariationModeMixin):
+@@ -858,10 +317,14 @@ class Operator(sv.ScaleVariationModeMixin):
              else:
                  self.op_members[n] = zero.copy()
 
@@ -601,12 +601,13 @@ index fe07ade9..0f58c9e5 100644
 +        cfg.as1 = self.as_list[1]
 +        cfg.as0 = self.as_list[0]
 +        cfg.py = ekors.ffi.cast("void *", cb_quad_ker_qcd.address)
++        cfg.method_num = self.ev_method
 +
 +    def run_op_integration(self, log_grid):
          """Run the integration for each grid point.
 
          Parameters
-@@ -876,18 +332,54 @@ class Operator(sv.ScaleVariationModeMixin):
+@@ -876,18 +339,53 @@ class Operator(sv.ScaleVariationModeMixin):
          """
          column = []
          k, logx = log_grid
@@ -622,7 +623,6 @@ index fe07ade9..0f58c9e5 100644
 +        cfg.is_log = self.int_disp.log
 +        cfg.logx = logx
 +        cfg.Lsv = np.log(self.xif2)
-+        cfg.method_num = 1
 +        cfg.ev_op_iterations = self.config["ev_op_iterations"]
 +        cfg.ev_op_max_order_qcd = self.config["ev_op_max_order"][0]
 +        cfg.sv_mode_num = self.sv_mode

src/eko/evolution_operator/operator_matrix_element.py.patch

@@ -1,5 +1,5 @@
 diff --git a/src/eko/evolution_operator/operator_matrix_element.py b/src/eko/evolution_operator/operator_matrix_element.py
-index 022f8073..017ec73d 100644
+index 022f8073..f6b3235d 100644
 --- a/src/eko/evolution_operator/operator_matrix_element.py
 +++ b/src/eko/evolution_operator/operator_matrix_element.py
 @@ -2,11 +2,12 @@
@@ -142,7 +142,7 @@ index 022f8073..017ec73d 100644
  class OperatorMatrixElement(Operator):
      r"""
      Internal representation of a single |OME|.
-@@ -291,41 +191,14 @@ class OperatorMatrixElement(Operator):
+@@ -291,41 +191,15 @@ class OperatorMatrixElement(Operator):
              )
          return labels
 
@@ -189,6 +189,7 @@ index 022f8073..017ec73d 100644
 +        cfg.as1 = self.a_s
 +        cfg.as0 = 0.0
 +        cfg.Lsv = np.log(self.xif2)
++        cfg.method_num = self.backward_method
 
      @property
      def a_s(self):

src/eko/evolution_operator/quad_ker.py

@@ -89,7 +89,7 @@ def cb_quad_ker_qcd(
     areas_x,
     areas_y,
     _L,
-    _method_num,
+    method_num,
     as1,
     as0,
     ev_op_iterations,
@@ -105,8 +105,7 @@ def cb_quad_ker_qcd(
     # combute basis functions
     areas = nb.carray(areas_raw, (areas_x, areas_y))
     pj = interpolation.evaluate_grid(n, is_log, logx, areas)
-    # TODO recover parameters
-    method = "iterate-exact"
+    method = method_num
     order = (order_qcd, 0)
     ev_op_max_order = (ev_op_max_order_qcd, 0)
     if is_singlet:
@@ -235,7 +234,7 @@ def cb_quad_ker_ome(
     areas_x,
     areas_y,
     L,
-    _method_num,
+    method_num,
     as1,
     _as0,
     _ev_op_iterations,
@@ -251,7 +250,7 @@ def cb_quad_ker_ome(
     # compute basis functions
     areas = nb.carray(areas_raw, (areas_x, areas_y))
     pj = interpolation.evaluate_grid(n, is_log, logx, areas)
-    # TODO recover parameters
+    backward_method = method_num
     order = (order_qcd, 0)
     if is_singlet:
         indices = {21: 0, 100: 1, 90: 2}
@@ -270,9 +269,6 @@ def cb_quad_ker_ome(
     if sv_mode == sv.Modes.exponentiated:
         A = sv.exponentiated.gamma_variation(A, order, nf, Lsv)
 
-    # TODO recover InversionMethod
-    backward_method = None
-
     # build the expansion in alpha_s depending on the strategy
     ker = build_ome(A, order, as1, backward_method)