Index.union(other) [source]
Form the union of two Index objects and sorts if possible. Parameters:
other : Index or array-like Returns:
union : Index Examples >>> idx1 = pd.Index([1, 2, 3, 4])
>>> idx2 = pd.Index([3, 4, 5, 6])
>>> idx1.union(idx2)
Int64Index([1, 2, 3, 4, 5, 6], dtype='int64')