Refactor _set_to_multihot (#670)

* fix : update _set_to_multihot function

* doc : update CHANGELOG.md

Author: sepandhaghighi

CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - `pycmError` class
 ### Changed
 - `__trapezoidal_numeric_integral__` function updated
+- `_set_to_multihot` function updated
 - Curve validation modified
 - Internal functions renamed
 - `README.md` modified

pycm/multilabel_cm.py

@@ -174,8 +174,4 @@ def _set_to_multihot(input_set: Set[Any], classes: List[Any]) -> List[int]:
     :param input_set: input set
     :param classes: ordered labels of classes
     """
-    result = [0] * len(classes)
-    for i, x in enumerate(classes):
-        if x in input_set:
-            result[i] = 1
-    return result
+    return [int(x in input_set) for x in classes]