[TASK] count same + test

Author: hzb-ps

bact_math_utils/misc.py

@@ -55,7 +55,7 @@ def __call__(self, iterable):
 class EnumerateUniqueJustSeen:
     """Return unique id's for the item and the item
 
-    Inspired by more_itertools.unique_lastseen.
+    Inspired by .
 
     Follows :func:`enumerate` API
 
@@ -128,6 +128,14 @@ def enumerate_changed_value_tuple(seq: Sequence) -> list:
     return data
 
 
+def enumerate_same_value_tuple(seq: Sequence) -> list:
+    mstep = CountSame()
+    return [cnt for cnt, val in mstep(zip(*seq))]
+
+
+def enumerate_same_value_pairs(val1: Sequence, val2: Sequence) -> list:
+    return enumerate_same_value_tuple((val1, val2))
+
 def enumerate_changed_value_pairs(val1: Sequence, val2: Sequence) -> list:
     """Emit a new number every time one of the values changes
 

tests/test_count_same.py

@@ -0,0 +1,29 @@
+import pytest
+from bact_math_utils.misc import CountSame, enumerate_same_value_pairs
+
+
+def test_count_same():
+    values = [42] * 3 + [23] + [42] * 2
+    step = CountSame()(values)
+    assert (0, 42) == next(step)
+    assert next(step) == (1, 42)
+    assert next(step) == (2, 42)
+
+    assert next(step) == (0, 23)
+
+    assert next(step) == (0, 42)
+    assert next(step) == (1, 42)
+
+
+def test_enumerate_same_pairs():
+    r = enumerate_same_value_pairs(
+        [0, 0, 0, 1, 1, 1, 1, 1, 1],
+        [0, 0, 0, 0, 0, 0, 2, 2, 2]
+    )
+    assert r == [0, 1, 2] * 3
+
+    r = enumerate_same_value_pairs(
+        [42, 42, 355/113, 355/133, 2.78, 2.78],
+        ["x", "x", "x", "y", "y", "y"]
+    )
+    assert r == [0, 1, 0, 0, 0, 1]