DOC: Enforce Numpy Docstring Validation for pandas.IntervalIndex.leng…

…th (#58671)

* DOC: add GL08 for pandas.IntervalIndex.length

* DOC: remove GL08 for pandas.IntervalIndex.length

ci/code_checks.sh

@@ -78,7 +78,6 @@ if [[ -z "$CHECK" || "$CHECK" == "docstrings" ]]; then
         -i "pandas.Grouper PR02" \
         -i "pandas.Index PR07" \
         -i "pandas.IntervalIndex.left GL08" \
-        -i "pandas.IntervalIndex.length GL08" \
         -i "pandas.IntervalIndex.set_closed RT03,SA01" \
         -i "pandas.IntervalIndex.to_tuples RT03,SA01" \
         -i "pandas.MultiIndex PR01" \

pandas/core/indexes/interval.py

@@ -924,6 +924,34 @@ def mid(self) -> Index:
 
     @property
     def length(self) -> Index:
+        """
+        Calculate the length of each interval in the IntervalIndex.
+
+        This method returns a new Index containing the lengths of each interval
+        in the IntervalIndex. The length of an interval is defined as the difference
+        between its end and its start.
+
+        Returns
+        -------
+        Index
+            An Index containing the lengths of each interval.
+
+        See Also
+        --------
+        Interval.length : Return the length of the Interval.
+
+        Examples
+        --------
+        >>> intervals = pd.IntervalIndex.from_arrays(
+        ...     [1, 2, 3], [4, 5, 6], closed="right"
+        ... )
+        >>> intervals.length
+        Index([3, 3, 3], dtype='int64')
+
+        >>> intervals = pd.IntervalIndex.from_tuples([(1, 5), (6, 10), (11, 15)])
+        >>> intervals.length
+        Index([4, 4, 4], dtype='int64')
+        """
         return Index(self._data.length, copy=False)
 
     # --------------------------------------------------------------------