Filter 2D tuples using python list comprehension
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Tuples are a group of items enclosed within ().
List comprehension can be used to filter a single-dimensional tuple.
After applying filter, we can get the output as a list or a tuple.
Below code illustrates how to filter a tuple of numbers, strings or dates.Output:Copiedfrom datetime import datetime numtuple = (5, 10, 20, 30, 40) #Filter numbers from tuple filterednumtuple = [num for num in numtuple if num > 15] print("Filtered tuple of numbers: " + str(tuple(filterednumtuple))) strtuple = ('James', 'Rory', 'Kevin') #Filter name Rory and Kevin filteredstrtuple = (st for st in strtuple if (st == 'Rory' or st == 'Kevin')) print("Filtered tuple of names: " + str(tuple(filteredstrtuple))) datetuple = ('2021/1/2', '2021/1/15', '2022/4/1', '2022/5/2') #Convert string dates to datetime objects dttuple = (datetime.strptime(dt, '%Y/%m/%d') for dt in datetuple) #Apply filter by month filtereddatetuple = (dt for dt in dttuple if dt.month == 1) #Convert datetime to str dates, if needed dates2strtuple = (datetime.strftime(dt1, '%Y/%m/%d') for dt1 in filtereddatetuple) print("Filtered dates tuple: " + str(tuple(dates2strtuple)))
Filtered tuple of numbers: (20, 30, 40)
Filtered tuple of names: ('Rory', 'Kevin')
Filtered dates tuple: ('2021/01/02', '2021/01/15')Check this sample if dates are having multiple formats.
Filter a list of string dates in different formats -
Two-dimensional tuples
If tuples are two-dimensional(tuples within tuples), some additional changes are required in the filter.
We have to access items within the tuple using positional parameters.
Output can be single or two-dimensional tuple.Output:Copiedfrom datetime import datetime numtuple = ( (1, 5), (2, 10), (3, 20), (4, 30), (5, 50) ) #Filter numbers. First part > 2 and second < 50 filterednum = ( (v[0], v[1]) for v in numtuple if (v[0] > 2 and v[1] < 50) ) print(tuple(filterednum)) strtuple = ( (1, 'Abe'), (2, 'Kim'), (3, 'Dan') ) #Filter names with 'a' filteredstr = (s[1] for s in strtuple if ('a' in s[1].lower()) ) print(tuple(filteredstr)) datetuple = ( (1, '2020/10/15'), (2, '2020/10/15'), (3, '2022/04/10'), (4, '2022/02/05') ) #String dates to datetime objects to apply filter dtitems = ( (d[0], datetime.strptime(d[1], '%Y/%m/%d')) for d in datetuple ) #Filter by year filtereddates = (d for d in dtitems if d[1].year == 2022) #Datetime to string dates conversion dates2str = ( (d[0], datetime.strftime(d[1], '%Y/%m/%d')) for d in filtereddates) print(tuple(dates2str))
((3, 20), (4, 30))
('Abe', 'Dan')
((3, '2022/04/10'), (4, '2022/02/05'))
