Fixed database typo and removed unnecessary class identifier.

venv/Lib/site-packages/skimage/util/tests/test_invert.py

@@ -0,0 +1,77 @@
+import numpy as np
+from skimage import dtype_limits
+from skimage.util.dtype import dtype_range
+from skimage.util import invert
+
+from skimage._shared.testing import assert_array_equal
+
+
+def test_invert_bool():
+    dtype = 'bool'
+    image = np.zeros((3, 3), dtype=dtype)
+    upper_dtype_limit = dtype_limits(image, clip_negative=False)[1]
+    image[1, :] = upper_dtype_limit
+    expected = np.zeros((3, 3), dtype=dtype) + upper_dtype_limit
+    expected[1, :] = 0
+    result = invert(image)
+    assert_array_equal(expected, result)
+
+
+def test_invert_uint8():
+    dtype = 'uint8'
+    image = np.zeros((3, 3), dtype=dtype)
+    upper_dtype_limit = dtype_limits(image, clip_negative=False)[1]
+    image[1, :] = upper_dtype_limit
+    expected = np.zeros((3, 3), dtype=dtype) + upper_dtype_limit
+    expected[1, :] = 0
+    result = invert(image)
+    assert_array_equal(expected, result)
+
+
+def test_invert_int8():
+    dtype = 'int8'
+    image = np.zeros((3, 3), dtype=dtype)
+    lower_dtype_limit, upper_dtype_limit = \
+        dtype_limits(image, clip_negative=False)
+    image[1, :] = lower_dtype_limit
+    image[2, :] = upper_dtype_limit
+    expected = np.zeros((3, 3), dtype=dtype)
+    expected[2, :] = lower_dtype_limit
+    expected[1, :] = upper_dtype_limit
+    expected[0, :] = -1
+    result = invert(image)
+    assert_array_equal(expected, result)
+
+
+def test_invert_float64_signed():
+    dtype = 'float64'
+    image = np.zeros((3, 3), dtype=dtype)
+    lower_dtype_limit, upper_dtype_limit = \
+        dtype_limits(image, clip_negative=False)
+    image[1, :] = lower_dtype_limit
+    image[2, :] = upper_dtype_limit
+    expected = np.zeros((3, 3), dtype=dtype)
+    expected[2, :] = lower_dtype_limit
+    expected[1, :] = upper_dtype_limit
+    result = invert(image, signed_float=True)
+    assert_array_equal(expected, result)
+
+
+def test_invert_float64_unsigned():
+    dtype = 'float64'
+    image = np.zeros((3, 3), dtype=dtype)
+    lower_dtype_limit, upper_dtype_limit = \
+        dtype_limits(image, clip_negative=True)
+    image[2, :] = upper_dtype_limit
+    expected = np.zeros((3, 3), dtype=dtype)
+    expected[0, :] = upper_dtype_limit
+    expected[1, :] = upper_dtype_limit
+    result = invert(image)
+    assert_array_equal(expected, result)
+
+
+def test_invert_roundtrip():
+    for t, limits in dtype_range.items():
+        image = np.array(limits, dtype=t)
+        expected = invert(invert(image))
+        assert_array_equal(image, expected)