DOC: improved docu of the value error msg changes

TST: adjusted panel test for change in value error msg in block manager TST: adjusted dataframe init test from json for change in value error msg in block manager

doc/source/whatsnew/v0.24.0.rst

@@ -1852,7 +1852,9 @@ Other
 ^^^^^
 
 - Bug where C variables were declared with external linkage causing import errors if certain other C libraries were imported before Pandas. (:issue:`24113`)
-- Switched shape in ``ValueError`` message when constructiong a :class:`DataFrame` with parameters ``columns`` and ``index`` not matching the shape of the input data. (:issue:`20742`)
+- Changed ``ValueError`` message when constructiong a :class:`DataFrame` with parameters ``columns`` and ``index`` not matching the shape of the input data. New message: "Shape of passed values is (``index``, ``columns``), indices imply (``index``, ``columns``)" (:issue:`20742`)
+- Changed ``ValueError`` message when constructiong a :class:`Panel` with parameters ``items``, ``major index`` and ``minor index`` not matching the shape of the input data. New message: "Shape of passed values is (``major``, ``minor``, ``items``), indices imply (``major``, ``minor``, ``items``)" (related to :issue:`20742`)
+
 
 .. _whatsnew_0.24.0.contributors:
 

pandas/core/internals/managers.py

@@ -1673,8 +1673,10 @@ def create_block_manager_from_arrays(arrays, names, axes):
 
 def construction_error(tot_items, block_shape, axes, e=None):
  """ raise a helpful message about our construction """
- passed = tuple(map(int, reversed([tot_items] + list(block_shape))))
- implied = tuple(map(int, reversed([len(ax) for ax in axes])))
+ passed = tuple(map(int, list(block_shape) + [tot_items]))
+
+ implied = [] if len(axes) == 0 \
+ else [len(ax) for ax in axes[1:] + [axes[0]]]
  if passed == implied and e is not None:
  raise e
  if block_shape[0] == 0:

pandas/tests/io/json/test_pandas.py

@@ -346,7 +346,7 @@ def test_frame_from_json_bad_data(self):
  json = StringIO('{"columns":["A","B"],'
  '"index":["2","3"],'
  '"data":[[1.0,"1"],[2.0,"2"],[null,"3"]]}')
- msg = r"Shape of passed values is \(2, 3\), indices imply \(2, 2\)"
+ msg = r"Shape of passed values is \(3, 2\), indices imply \(2, 2\)"
  with pytest.raises(ValueError, match=msg):
  read_json(json, orient="split")
 

pandas/tests/test_panel.py

@@ -1143,23 +1143,11 @@ def test_from_dict_mixed_orient(self):
  assert panel['A'].values.dtype == np.float64
 
  def test_constructor_error_msgs(self):
- msg = (r"Shape of passed values is \(3, 4, 5\), "
- r"indices imply \(4, 5, 5\)")
+ msg = (r"Shape of passed values is \(4, 5, 3\), "
+ r"indices imply \(5, 6, 4\)")
  with pytest.raises(ValueError, match=msg):
  Panel(np.random.randn(3, 4, 5),
- lrange(4), lrange(5), lrange(5))
-
- msg = (r"Shape of passed values is \(3, 4, 5\), "
- r"indices imply \(5, 4, 5\)")
- with pytest.raises(ValueError, match=msg):
- Panel(np.random.randn(3, 4, 5),
- lrange(5), lrange(4), lrange(5))
-
- msg = (r"Shape of passed values is \(3, 4, 5\), "
- r"indices imply \(5, 5, 4\)")
- with pytest.raises(ValueError, match=msg):
- Panel(np.random.randn(3, 4, 5),
- lrange(5), lrange(5), lrange(4))
+ lrange(4), lrange(5), lrange(6))
 
  def test_conform(self):
  df = self.panel['ItemA'][:-5].filter(items=['A', 'B'])