Upgrade table wrappers to public classes

These are going to be commonly used by users so they shouldn't
be hidden as private classes in the sim module.

urbansim/sim/simulation.py

@@ -32,7 +32,7 @@ class SimulationError(Exception):
     pass
 
 
-class _DataFrameWrapper(object):
+class DataFrameWrapper(object):
     """
     Wraps a DataFrame so it can provide certain columns and handle
     computed columns.
@@ -144,7 +144,7 @@ def __len__(self):
         return len(self._frame)
 
 
-class _TableFuncWrapper(object):
+class TableFuncWrapper(object):
     """
     Wrap a function that provides a DataFrame.
 
@@ -224,7 +224,7 @@ def to_frame(self, columns=None):
 
         """
         frame = self._call_func()
-        return _DataFrameWrapper(self.name, frame).to_frame(columns)
+        return DataFrameWrapper(self.name, frame).to_frame(columns)
 
     def get_column(self, column_name):
         """
@@ -251,7 +251,7 @@ def __len__(self):
         return self._len
 
 
-class _TableSourceWrapper(_TableFuncWrapper):
+class TableSourceWrapper(TableFuncWrapper):
     """
     Wraps a function that returns a DataFrame. After the function
     is evaluated the returned DataFrame replaces the function in the
@@ -266,7 +266,7 @@ class _TableSourceWrapper(_TableFuncWrapper):
     def convert(self):
         """
         Evaluate the wrapped function, store the returned DataFrame as a
-        table, and return the new _DataFrameWrapper instance created.
+        table, and return the new DataFrameWrapper instance created.
 
         """
         frame = self._call_func()
@@ -430,13 +430,13 @@ def add_table(table_name, table):
 
     Returns
     -------
-    wrapped : `_DataFrameWrapper` or `_TableFuncWrapper`
+    wrapped : `DataFrameWrapper` or `TableFuncWrapper`
 
     """
     if isinstance(table, pd.DataFrame):
-        table = _DataFrameWrapper(table_name, table)
+        table = DataFrameWrapper(table_name, table)
     elif isinstance(table, Callable):
-        table = _TableFuncWrapper(table_name, table)
+        table = TableFuncWrapper(table_name, table)
     else:
         raise TypeError('table must be DataFrame or function.')
 
@@ -475,10 +475,10 @@ def add_table_source(table_name, func):
 
     Returns
     -------
-    wrapped : `_TableSourceWrapper`
+    wrapped : `TableSourceWrapper`
 
     """
-    wrapped = _TableSourceWrapper(table_name, func)
+    wrapped = TableSourceWrapper(table_name, func)
     _TABLES[table_name] = wrapped
     return wrapped
 
@@ -506,7 +506,7 @@ def get_table(table_name):
 
     Returns
     -------
-    table : _DataFrameWrapper or _TableFuncWrapper
+    table : `DataFrameWrapper`, `TableFuncWrapper`, or `TableSourceWrapper`
 
     """
     if table_name in _TABLES:
@@ -804,7 +804,7 @@ def merge_tables(target, tables, columns=None):
     ----------
     target : str
         Name of the table onto which tables will be merged.
-    tables : list of _DataFrameWrapper or _TableFuncWrapper
+    tables : list of `DataFrameWrapper` or `TableFuncWrapper`
         All of the tables to merge. Should include the target table.
     columns : list of str, optional
         If given, columns will be mapped to `tables` and only those columns

urbansim/sim/tests/test_mergetables.py

@@ -9,7 +9,7 @@
 
 @pytest.fixture
 def dfa():
-    return sim._DataFrameWrapper('a', pd.DataFrame(
+    return sim.DataFrameWrapper('a', pd.DataFrame(
         {'a1': [1, 2, 3],
          'a2': [4, 5, 6],
          'a3': [7, 8, 9]},
@@ -18,7 +18,7 @@ def dfa():
 
 @pytest.fixture
 def dfz():
-    return sim._DataFrameWrapper('z', pd.DataFrame(
+    return sim.DataFrameWrapper('z', pd.DataFrame(
         {'z1': [90, 91],
          'z2': [92, 93],
          'z3': [94, 95],
@@ -29,7 +29,7 @@ def dfz():
 
 @pytest.fixture
 def dfb():
-    return sim._DataFrameWrapper('b', pd.DataFrame(
+    return sim.DataFrameWrapper('b', pd.DataFrame(
         {'b1': range(10, 15),
          'b2': range(15, 20),
          'a_id': ['ac', 'ac', 'ab', 'aa', 'ab'],
@@ -39,7 +39,7 @@ def dfb():
 
 @pytest.fixture
 def dfc():
-    return sim._DataFrameWrapper('c', pd.DataFrame(
+    return sim.DataFrameWrapper('c', pd.DataFrame(
         {'c1': range(20, 30),
          'c2': range(30, 40),
          'b_id': ['ba', 'bd', 'bb', 'bc', 'bb', 'ba', 'bb', 'bc', 'bd', 'bb']},
@@ -48,14 +48,14 @@ def dfc():
 
 @pytest.fixture
 def dfg():
-    return sim._DataFrameWrapper('g', pd.DataFrame(
+    return sim.DataFrameWrapper('g', pd.DataFrame(
         {'g1': [1, 2, 3]},
         index=['ga', 'gb', 'gc']))
 
 
 @pytest.fixture
 def dfh():
-    return sim._DataFrameWrapper('h', pd.DataFrame(
+    return sim.DataFrameWrapper('h', pd.DataFrame(
         {'h1': range(10, 15),
          'g_id': ['ga', 'gb', 'gc', 'ga', 'gb']},
         index=['ha', 'hb', 'hc', 'hd', 'he']))

urbansim/sim/tests/test_simulation.py

@@ -287,7 +287,7 @@ def source():
         return df
 
     table = sim.get_table('source')
-    assert isinstance(table, sim._TableSourceWrapper)
+    assert isinstance(table, sim.TableSourceWrapper)
 
     test_df = table.to_frame()
     pdt.assert_frame_equal(test_df, df)
@@ -296,7 +296,7 @@ def source():
     pdt.assert_index_equal(table.index, df.index)
 
     table = sim.get_table('source')
-    assert isinstance(table, sim._DataFrameWrapper)
+    assert isinstance(table, sim.DataFrameWrapper)
 
     test_df = table.to_frame()
     pdt.assert_frame_equal(test_df, df)
@@ -308,10 +308,10 @@ def source():
         return df
 
     table = sim.get_table('source')
-    assert isinstance(table, sim._TableSourceWrapper)
+    assert isinstance(table, sim.TableSourceWrapper)
 
     table = table.convert()
-    assert isinstance(table, sim._DataFrameWrapper)
+    assert isinstance(table, sim.DataFrameWrapper)
     pdt.assert_frame_equal(table.to_frame(), df)
 
     table2 = sim.get_table('source')