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convert this List Comprehensions to loop - jacklee26 - Oct-20-2022 Does anyone know how to convert this List Comprehensions to normal for loop code: results = ['A' , 'B', 'C' , 'D'] ]for i in [results[c:c+2] for c in range(0,len(results)) if c%2 == 0]: print(*i)output: A B C D RE: convert this List Comprehensions to loop - deanhystad - Oct-20-2022 The ] before the for loop is an error. Converting a comprehension to a loop si pretty straight forward. Write the loops backwards. for i in [results[c:c+2] for c in range(0,len(results)) if c%2 == 0]becomes temp = [] for c in range(0, len(results)): if c % 2 == 0: temp.append(results[c:c+2]) for i in temp: print(*i)I like this way better: results = iter(["A", "B", "C", "D"]) for i in zip(results, results): print(*i) RE: convert this List Comprehensions to loop - rob101 - Oct-20-2022 As already stated, there's an error (a typo, maybe?) This is how I would do it: results = ['A', 'B', 'C', 'D'] for index, c in enumerate(results): if index % 2 == 0: print(*results[index:index + 2]) I've used index rather than i , but it's the same thing.
RE: convert this List Comprehensions to loop - jacklee26 - Oct-20-2022 Thanks. It was a typo. Basely I was trying to find some solution to nth index of a list and add a new line. For example, if my list has hundreds of data, I just wish new line after 2 columns. So I went to StackOverflow and found this solution, but I'm unfamiliar with list Comprehension. Thanks for all the help. RE: convert this List Comprehensions to loop - jacklee26 - Oct-21-2022 (Oct-20-2022, 04:46 AM)rob101 Wrote: As already stated, there's an error (a typo, maybe?) HI rob101, Is it possible to write it into a text file, instead of print? RE: convert this List Comprehensions to loop - rob101 - Oct-21-2022 (Oct-21-2022, 01:14 PM)jacklee26 Wrote: HI rob101, Yes; you simply add a file handler and redirect the print() function:with open('output.txt', 'a') as output: results = ['A', 'B', 'C', 'D'] for index, c in enumerate(results): if index % 2 == 0: print(*results[index:index + 2], file=output)That will create a file called output.txt within the same directory from which the python script is run.
RE: convert this List Comprehensions to loop - deanhystad - Oct-21-2022 Use range with a step instead of enumerate and modulo. results = ['A', 'B', 'C', 'D'] for index in range(0, len(results), 2): print(*results[index:index + 2]) RE: convert this List Comprehensions to loop - rob101 - Oct-21-2022 I was sticking to the original code (with regard to modulo). Also I've adopted the this practice: [Basic] Never use "for i in range(len(sequence)): That said, I agree that is a neater solution, but you can drop the 0 , right? It's implied.
RE: convert this List Comprehensions to loop - deanhystad - Oct-21-2022 The call is range(stop) or range(start, stop[, step]). If you want to use a step you need to specify the start. All arguments are positional. |