From 5b19ffc0d13b0c3f9f036868dc4d035042d0aa5b Mon Sep 17 00:00:00 2001
From: Paul Natsuo Kishimoto <mail@paul.kishimoto.name>
Date: Tue, 11 Feb 2020 16:49:38 +0100
Subject: [PATCH] Adjust data structure used by Model.initialize_items

---
 ixmp/model/base.py    | 12 ++++++------
 ixmp/model/dantzig.py | 26 +++++++++++++-------------
 ixmp/model/gams.py    |  1 -
 3 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/ixmp/model/base.py b/ixmp/model/base.py
index 7ff41bdd7..bb7bcfce3 100644
--- a/ixmp/model/base.py
+++ b/ixmp/model/base.py
@@ -57,10 +57,10 @@ def initialize_items(cls, scenario, items):
         ----------
         scenario : .Scenario
             Scenario object to initialize.
-        items : list of dict
-            Each entry is one ixmp item (set, parameter, equation, or variable)
-            to initialize. Each dict **must** have the key 'ix_type'; one of
-            'set', 'par', 'equ', or 'var'; any other entries are keyword
+        items : dict of (str -> dict)
+            Each key is the name of an ixmp item (set, parameter, equation, or
+            variable) to initialize. Each dict **must** have the key 'ix_type';
+            one of 'set', 'par', 'equ', or 'var'; any other entries are keyword
             arguments to the methods :meth:`.init_set` etc.
 
         See also
@@ -79,7 +79,7 @@ def initialize_items(cls, scenario, items):
             # attempt raises an exception
             pass
 
-        for item_info in items:
+        for name, item_info in items.items():
             # Copy so that pop() below does not modify *items*
             item_info = item_info.copy()
 
@@ -89,7 +89,7 @@ def initialize_items(cls, scenario, items):
 
             try:
                 # Add the item
-                init_method(**item_info)
+                init_method(name=name, **item_info)
             except ValueError:
                 # Item already exists
                 pass
diff --git a/ixmp/model/dantzig.py b/ixmp/model/dantzig.py
index ffdaeb0c4..9827bc68e 100644
--- a/ixmp/model/dantzig.py
+++ b/ixmp/model/dantzig.py
@@ -7,26 +7,26 @@
 from .gams import GAMSModel
 
 
-ITEMS = (
+ITEMS = {
     # Plants
-    dict(ix_type='set', name='i'),
+    'i': dict(ix_type='set'),
     # Markets
-    dict(ix_type='set', name='j'),
+    'j': dict(ix_type='set'),
     # Capacity of plant i in cases
-    dict(ix_type='par', name='a', idx_sets=['i']),
+    'a': dict(ix_type='par', idx_sets=['i']),
     # Demand at market j in cases
-    dict(ix_type='par', name='b', idx_sets=['j']),
+    'b': dict(ix_type='par', idx_sets=['j']),
     # Distance between plant i and market j
-    dict(ix_type='par', name='d', idx_sets=['i', 'j']),
+    'd': dict(ix_type='par', idx_sets=['i', 'j']),
     # Transport cost per case per 1000 miles
-    dict(ix_type='par', name='f', idx_sets=None),
+    'f': dict(ix_type='par', idx_sets=None),
     # Decision variables and equations
-    dict(ix_type='var', name='x', idx_sets=['i', 'j']),
-    dict(ix_type='var', name='z', idx_sets=None),
-    dict(ix_type='equ', name='cost', idx_sets=None),
-    dict(ix_type='equ', name='demand', idx_sets=['j']),
-    dict(ix_type='equ', name='supply', idx_sets=['i']),
-)
+    'x': dict(ix_type='var', idx_sets=['i', 'j']),
+    'z': dict(ix_type='var', idx_sets=None),
+    'cost': dict(ix_type='equ', idx_sets=None),
+    'demand': dict(ix_type='equ', idx_sets=['j']),
+    'supply': dict(ix_type='equ', idx_sets=['i']),
+}
 
 DATA = {
     'i': ['seattle', 'san-diego'],
diff --git a/ixmp/model/gams.py b/ixmp/model/gams.py
index 876b13221..2d7026c5d 100644
--- a/ixmp/model/gams.py
+++ b/ixmp/model/gams.py
@@ -5,7 +5,6 @@
 
 
 from ixmp.backend import ItemType
-from ixmp.backend.jdbc import JDBCBackend
 from ixmp.model.base import Model
 from ixmp.utils import as_str_list