Merge pull request #167 from sciris/fixes-mar2021

Date improvements

CHANGELOG.rst

@@ -6,6 +6,13 @@ All notable changes to this project will be documented in this file.
 By import convention, components of the Sciris library are listed beginning with ``sc.``, e.g. ``sc.odict()``.
 
 
+Version 1.0.2 (2021-03-10)
+---------------------------
+1. Fixed bug (introduced in version 1.0.1) with ``sc.readdate()`` returning only the first element of a list of a dates.
+2. Fixed bug (introduced in version 1.0.1) with ``sc.date()`` treating an integer as a timestamp rather than an integer number of days when a start day is supplied.
+3. Updated ``sc.readdate()``, ``sc.date()``, and ``sc.day()`` to always return consistent output types (e.g. if an array is supplied as an input, an array is supplied as an output).
+
+
 Version 1.0.1 (2021-03-01)
 ---------------------------
 1. Fixed bug with Matplotlib 3.4.0 also defining colormap ``'turbo'``, which caused Sciris to fail to load.

sciris/sc_utils.py

@@ -1518,6 +1518,42 @@ def getdate(obj=None, astype='str', dateformat=None):
         return None # Should not be possible to get to this point
 
 
+def _sanitize_iterables(obj, *args):
+    '''
+    Take input as a list, array, or non-iterable type, along with one or more
+    arguments, and return a list, along with information on what the input types
+    were.
+
+    **Examples**::
+
+        _sanitize_iterables(1, 2, 3)             # Returns [1,2,3], False, False
+        _sanitize_iterables([1, 2], 3)           # Returns [1,2,3], True, False
+        _sanitize_iterables(np.array([1, 2]), 3) # Returns [1,2,3], True, True
+        _sanitize_iterables(np.array([1, 2, 3])) # Returns [1,2,3], False, True
+    '''
+    is_list = isinstance(obj, list) or len(args)>0 # If we're given a list of args, treat it like a list
+    is_array = isinstance(obj, np.ndarray) # Check if it's an array
+    if is_array: # If it is, convert it to a list
+        obj = obj.tolist()
+    objs = dcp(promotetolist(obj)) # Ensure it's a list, and deepcopy to avoid mutability
+    objs.extend(args) # Add on any arguments
+    return objs, is_list, is_array
+
+
+def _sanitize_output(obj, is_list, is_array, dtype=None):
+    '''
+    The companion to _sanitize_iterables, convert the object back to the original
+    type supplied.
+    '''
+    if is_array:
+        output = np.array(obj, dtype=dtype)
+    elif not is_list and len(obj) == 1:
+        output = obj[0]
+    else:
+        output = obj
+    return output
+
+
 def readdate(datestr=None, *args, dateformat=None, return_defaults=False):
     '''
     Convenience function for loading a date from a string. If dateformat is None,
@@ -1561,9 +1597,10 @@ def readdate(datestr=None, *args, dateformat=None, return_defaults=False):
         for f,fmt in enumerate(format_list):
             formats_to_try[f'User supplied {f}'] = fmt
 
+    # Ensure everything is in a consistent format
+    datestrs, is_list, is_array = _sanitize_iterables(datestr, *args)
+
     # Actually process the dates
-    datestrs = promotetolist(datestr)
-    datestrs.extend(args)
     dateobjs = []
     for datestr in datestrs: # Iterate over them
         dateobj = None
@@ -1585,26 +1622,27 @@ def readdate(datestr=None, *args, dateformat=None, return_defaults=False):
                 raise ValueError(errormsg)
         dateobjs.append(dateobj)
 
-    # If only a single date was supplied, return just that; else return the list
-    if not isinstance(datestr, list) and not len(args):
-        return dateobjs[0]
-    else:
-        return dateobjs
+    # If only a single date was supplied, return just that; else return the list/array
+    output = _sanitize_output(dateobjs, is_list, is_array, dtype=object)
+    return output
 
 
 def date(obj, *args, start_date=None, dateformat=None, as_date=True):
     '''
-    Convert a string or a datetime object to a date object. To convert to an integer
-    from the start day, it is recommended you supply a start date, or use sc.date()
-    instead; otherwise, it will calculate the date counting days from 2020-01-01.
-    This means that the output of sc.date() will not necessarily match the output
-    of sc.date() for an integer input.
+    Convert any reasonable object -- a string, integer, or datetime object, or
+    list/array of any of those -- to a date object. To convert an integer to a
+    date, you must supply a start date.
+
+    Caution: while this function and readdate() are similar, and indeed this function
+    calls readdate() if the input is a string, in this function an integer is treated
+    as a number of days from start_day, while for readdate() it is treated as a
+    timestamp in seconds.
 
     Args:
-        obj (str, int, float, date, datetime, list, array): the object to convert
-        args (str, int, float, date, datetime): additional objects to convert
+        obj (str, int, date, datetime, list, array): the object to convert
+        args (str, int, date, datetime): additional objects to convert
         start_date (str, date, datetime): the starting date, if an integer is supplied
-        dateformat (str): the format to return the date in
+        dateformat (str): the format to return the date in, if returning a string
         as_date (bool): whether to return as a datetime date instead of a string
 
     Returns:
@@ -1613,24 +1651,16 @@ def date(obj, *args, start_date=None, dateformat=None, as_date=True):
     **Examples**::
 
         sc.date('2020-04-05') # Returns datetime.date(2020, 4, 5)
-        sc.date('2020-04-14', start_date='2020-04-04', as_date=False) # Returns 10
         sc.date([35,36,37], as_date=False) # Returns ['2020-02-05', '2020-02-06', '2020-02-07']
 
     New in version 1.0.0.
     '''
-
+    # Convert to list and handle other inputs
     if obj is None:
         return None
-
-    # Convert to list and handle other inputs
-    if isinstance(obj, np.ndarray):
-        obj = obj.tolist() # If it's an array, convert to a list
-    obj = promotetolist(obj) # Ensure it's iterable
-    obj.extend(args)
     if dateformat is None:
         dateformat = '%Y-%m-%d'
-    if start_date is None:
-        start_date = '2020-01-01'
+    obj, is_list, is_array = _sanitize_iterables(obj, *args)
 
     dates = []
     for d in obj:
@@ -1640,10 +1670,10 @@ def date(obj, *args, start_date=None, dateformat=None, as_date=True):
         try:
             if type(d) == dt.date: # Do not use isinstance, since must be the exact type
                 pass
-            elif isstring(d) or isnumber(d):
-                d = readdate(d).date()
             elif isinstance(d, dt.datetime):
                 d = d.date()
+            elif isstring(d):
+                d = readdate(d).date()
             elif isnumber(d):
                 if start_date is None:
                     errormsg = f'To convert the number {d} to a date, you must supply start_date'
@@ -1661,10 +1691,8 @@ def date(obj, *args, start_date=None, dateformat=None, as_date=True):
             raise ValueError(errormsg)
 
     # Return an integer rather than a list if only one provided
-    if len(dates)==1:
-        dates = dates[0]
-
-    return dates
+    output = _sanitize_output(dates, is_list, is_array, dtype=object)
+    return output
 
 
 def day(obj, *args, start_day=None):
@@ -1687,16 +1715,10 @@ def day(obj, *args, start_day=None):
     New in version 1.0.0.
     '''
 
-    # Do not process a day if it's not supplied
+    # Do not process a day if it's not supplied, and ensure it's a list
     if obj is None:
         return None
-
-    # Convert to list
-    if isstring(obj) or isnumber(obj) or isinstance(obj, (dt.date, dt.datetime)):
-        obj = promotetolist(obj) # Ensure it's iterable
-    elif isinstance(obj, np.ndarray):
-        obj = obj.tolist() # Convert to list if it's an array
-    obj.extend(args)
+    obj, is_list, is_array = _sanitize_iterables(obj, *args)
 
     days = []
     for d in obj:
@@ -1721,10 +1743,8 @@ def day(obj, *args, start_day=None):
                 raise ValueError(errormsg)
 
     # Return an integer rather than a list if only one provided
-    if len(days)==1:
-        days = days[0]
-
-    return days
+    output = _sanitize_output(days, is_list, is_array, dtype=object)
+    return output
 
 
 def daydiff(*args):
@@ -1772,12 +1792,11 @@ def daterange(start_date, end_date, inclusive=True, as_date=False, dateformat=No
 
     New in version 1.0.0.
     '''
-    start_day = day(start_date)
-    end_day = day(end_date)
+    end_day = day(end_date, start_day=start_date)
     if inclusive:
         end_day += 1
-    days = np.arange(start_day, end_day)
-    dates = date(days, as_date=as_date, dateformat=dateformat)
+    days = list(range(end_day))
+    dates = date(days, start_date=start_date, as_date=as_date, dateformat=dateformat)
     return dates
 
 

sciris/sc_version.py

@@ -4,6 +4,6 @@
 
 __all__ = ['__version__', '__versiondate__', '__license__']
 
-__version__      = '1.0.1'
-__versiondate__  = '2021-03-01'
+__version__      = '1.0.2'
+__versiondate__  = '2021-03-10'
 __license__      = 'Sciris %s (%s) -- (c) Sciris.org' % (__version__, __versiondate__)

tests/test_utils.py

@@ -269,24 +269,50 @@ def test_types():
 def test_readdate():
     sc.heading('Test string-to-date conversion')
 
-    string1 = '2020-Mar-21'
-    string2 = '2020-03-21'
-    string3 = 'Sat Mar 21 23:13:56 2020'
+    # Basic tests
+    string0 = '2020-Mar-21'
+    string1 = '2020-03-21'
+    string2 = 'Sat Mar 21 23:13:56 2020'
+    string3 = '2020-04-04'
+    dateobj0 = sc.readdate(string0)
     dateobj1 = sc.readdate(string1)
     dateobj2 = sc.readdate(string2)
-    sc.readdate(string3)
-    assert dateobj1 == dateobj2
+    assert dateobj0 == dateobj1
     with pytest.raises(ValueError):
         sc.readdate('Not a date')
 
-    # Automated tests
+    # Test different formats
+    strlist = [string0, string0, string2]
+    strarr = np.array(strlist)
+    fromlist = sc.readdate(strlist, string3)
+    fromarr = sc.readdate(strarr, string3)
+    assert fromlist[2] == dateobj2
+    assert sc.readdate(*strlist)[2] == dateobj2
+    assert fromarr[2] == dateobj2
+    assert len(fromlist) == len(fromarr) == len(strlist) + 1 == len(strarr) + 1
+    assert isinstance(fromlist, list)
+    assert isinstance(fromarr, np.ndarray)
+
+    # Test timestamps
+    now_datetime = sc.now()
+    now_timestamp = sc.readdate(sc.tic())
+    assert now_timestamp.day == now_datetime.day
+
+    # Format tests
     formats_to_try = sc.readdate(return_defaults=True)
     for key,fmt in formats_to_try.items():
         datestr = sc.getdate(dateformat=fmt)
         dateobj = sc.readdate(datestr, dateformat=fmt)
         print(f'{key:15s} {fmt:22s}: {dateobj}')
 
-    return dateobj1
+    # Basic tests
+    assert sc.sc_utils._sanitize_iterables(1)                   == ([1],     False, False)
+    assert sc.sc_utils._sanitize_iterables(1, 2, 3)             == ([1,2,3], True, False)
+    assert sc.sc_utils._sanitize_iterables([1, 2], 3)           == ([1,2,3], True, False)
+    assert sc.sc_utils._sanitize_iterables(np.array([1, 2]), 3) == ([1,2,3], True, True)
+    assert sc.sc_utils._sanitize_iterables(np.array([1, 2, 3])) == ([1,2,3], False, True)
+
+    return dateobj0
 
 
 def test_dates():
@@ -295,19 +321,29 @@ def test_dates():
 
     print('\nTesting date')
     o.date1 = sc.date('2020-04-05') # Returns datetime.date(2020, 4, 5)
-    o.date2 = sc.date('2020-04-14', start_date='2020-04-04', as_date=False) # Returns 10
-    o.date3 = sc.date([35,36,37], as_date=False) # Returns ['2020-02-05', '2020-02-06', '2020-02-07']
+    o.date2 = sc.date(sc.readdate('2020-04-14'), as_date=False, dateformat='%Y%m') # Returns '202004'
+    o.date3 = sc.date([35,36,37], start_date='2020-01-01', as_date=False) # Returns ['2020-02-05', '2020-02-06', '2020-02-07']
+    with pytest.raises(ValueError):
+        sc.date([10,20]) # Can't convert an integer without a start date
+    assert o.date1.month == 4
+    assert o.date2 == '202004'
+    assert len(o.date3) == 3
+    assert o.date3[0] =='2020-02-05'
 
     print('\nTesting day')
     o.day = sc.day('2020-04-04') # Returns 94
     assert o.day == 94
+    assert sc.day('2020-03-01') > sc.day('2021-03-01') # Because of the leap day
+    assert sc.day('2020-03-01', start_day='2020-01-01') < sc.day('2021-03-01', start_day='2020-01-01') # Because years
 
     print('\nTesting daydiff')
     o.diff  = sc.daydiff('2020-03-20', '2020-04-05') # Returns 16
     o.diffs = sc.daydiff('2020-03-20', '2020-04-05', '2020-05-01') # Returns [16, 26]
+    assert len(o.diffs) == 2
 
     print('\nTesting daterange')
     o.dates = sc.daterange('2020-03-01', '2020-04-04')
+    assert len(o.dates) == 35
 
     print('\nTesting elapsedtimestr')
     now = sc.now()