PERF: improve conversion to BooleanArray from int/float array

doc/source/whatsnew/v1.0.0.rst

@@ -156,7 +156,7 @@ type dedicated to boolean data that can hold missing values. With the default
 ``'bool`` data type based on a numpy bool array, the column can only hold
 True or False values and not missing values. This new :class:`BooleanDtype`
 can store missing values as well by keeping track of this in a separate mask.
-(:issue:`29555`)
+(:issue:`29555`, :issue:`30095`)
 
 .. ipython:: python
 

pandas/core/arrays/boolean.py

@@ -130,9 +130,19 @@ def coerce_to_array(values, mask=None, copy: bool = False):
  if isinstance(values, np.ndarray) and values.dtype == np.bool_:
  if copy:
  values = values.copy()
+ elif isinstance(values, np.ndarray) and values.dtype in (np.int_, np.float_):
+ mask_values = isna(values)
+
+ values_bool = np.zeros(len(values), dtype=bool)
+ values_bool[~mask_values] = values[~mask_values].astype(bool)
+
+ if not np.all(
+ values_bool[~mask_values].astype(values.dtype) == values[~mask_values]
+ ):
+ raise TypeError("Need to pass bool-like values")
+
+ values = values_bool
  else:
- # TODO conversion from integer/float ndarray can be done more efficiently
- # (avoid roundtrip through object)
  values_object = np.asarray(values, dtype=object)
 
  inferred_dtype = lib.infer_dtype(values_object, skipna=True)

pandas/tests/arrays/test_boolean.py

@@ -133,24 +133,37 @@ def test_to_boolean_array_error(values):
  pd.array(values, dtype="boolean")
 
 
-def test_to_boolean_array_integer_like():
- # integers of 0's and 1's
- result = pd.array([1, 0, 1, 0], dtype="boolean")
+def test_to_boolean_array_from_integer_array():
+ result = pd.array(np.array([1, 0, 1, 0]), dtype="boolean")
  expected = pd.array([True, False, True, False], dtype="boolean")
  tm.assert_extension_array_equal(result, expected)
 
- result = pd.array(np.array([1, 0, 1, 0]), dtype="boolean")
+ # with missing values
+ result = pd.array(np.array([1, 0, 1, None]), dtype="boolean")
+ expected = pd.array([True, False, True, None], dtype="boolean")
  tm.assert_extension_array_equal(result, expected)
 
+
+def test_to_boolean_array_from_float_array():
  result = pd.array(np.array([1.0, 0.0, 1.0, 0.0]), dtype="boolean")
+ expected = pd.array([True, False, True, False], dtype="boolean")
  tm.assert_extension_array_equal(result, expected)
 
  # with missing values
- result = pd.array([1, 0, 1, None], dtype="boolean")
+ result = pd.array(np.array([1.0, 0.0, 1.0, np.nan]), dtype="boolean")
  expected = pd.array([True, False, True, None], dtype="boolean")
  tm.assert_extension_array_equal(result, expected)
 
- result = pd.array(np.array([1.0, 0.0, 1.0, np.nan]), dtype="boolean")
+
+def test_to_boolean_array_integer_like():
+ # integers of 0's and 1's
+ result = pd.array([1, 0, 1, 0], dtype="boolean")
+ expected = pd.array([True, False, True, False], dtype="boolean")
+ tm.assert_extension_array_equal(result, expected)
+
+ # with missing values
+ result = pd.array([1, 0, 1, None], dtype="boolean")
+ expected = pd.array([True, False, True, None], dtype="boolean")
  tm.assert_extension_array_equal(result, expected)