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+--- Thread: Deleting duplicates in tuples (/thread-23179.html)
Deleting duplicates in tuples - Den - Dec-14-2019
I have a list of tuples, and I am trying to delete some tuples of the list based on their first element: if the first element is the same first element of the next tuple, then the second tuple, which contains that same first element, should be deleted. I tried doing it through an iterative loop, but it doesn't completely work. Some duplicates are still left in the list.
for tuple in list:
index_of_the_first_tuple=list.index(tuple)
if tuple[0] in list[index_of_the_first_tuple+1]:
list.pop(index_of_the_first_tuple+1)
RE: Deleting duplicates in tuples - Gribouillis - Dec-14-2019
Den Wrote:then the second tuple, which contains that same first element, should be deleted.What about the third tuple containing the same first element. Does it need to be deleted too?
RE: Deleting duplicates in tuples - ichabod801 - Dec-14-2019
You shouldn't use the names of Python built-ins (like tuple and list) for you variable names, because then you lose access to the built-ins. You should also avoid modifying a list that you are iterating over. That's probably why your program is failing. You should build a new list without the items you want to remove:
new_data = data[:1]
for item in data[1:]:
if item[0] != new_data[-1][0]:
new_data.append(item)
data = new_dataNote that this will delete the third and succeeding duplicates taht Gribouillis mentioned. Also, if the list is not sorted, it will not remove all of the duplicates.