improve input argument preprocessing

Author: Si Wei How

pandas/tseries/offsets.py

@@ -17,6 +17,7 @@
 from pandas.util._decorators import Appender, Substitution, cache_readonly
 
 from pandas.core.dtypes.generic import ABCPeriod
+from pandas.core.dtypes.inference import _iterable_not_string
 
 from pandas.core.tools.datetimes import to_datetime
 
@@ -579,12 +580,18 @@ class BusinessHourMixin(BusinessMixin):
 
     def __init__(self, start='09:00', end='17:00', offset=timedelta(0)):
         # must be validated here to equality check
-        if not isinstance(start, (tuple, list)):
-            start = (start,)
-        if not isinstance(end, (tuple, list)):
-            end = (end,)
-        start = tuple(map(liboffsets._validate_business_time, start))
-        end = tuple(map(liboffsets._validate_business_time, end))
+        if _iterable_not_string(start):
+            start = np.asarray(start)
+        else:
+            start = np.array([start])
+        if _iterable_not_string(end):
+            end = np.asarray(end)
+        else:
+            end = np.array([end])
+  
+        vliboffsets = np.vectorize(liboffsets._validate_business_time)
+        start = vliboffsets(start)
+        end = vliboffsets(end)
 
         # Validation of input
         if len(start) != len(end):
@@ -594,8 +601,8 @@ def __init__(self, start='09:00', end='17:00', offset=timedelta(0)):
 
         # sort starting and ending time by starting time
         index = np.argsort(start)
-        start = tuple(np.array(start)[index])
-        end = tuple(np.array(end)[index])
+        start = tuple(start[index])
+        end = tuple(end[index])
 
         total_secs = 0
         for i in range(num_openings):