Get index of repeated elements in list python

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WebApr 25, 2015 · You can use the count () method from the list object to get a count equal to 1: >>> A= [1, 2, 3, 2, 5, 1] >>> unique= [i for i in A if A.count (i)==1] >>> unique [3, 5] Alternatively the Counter () class from the collections module can be used: A = [1, 2, 3, 2, 5, 1] c = Counter (A) print [key for key, count in c.iteritems () if count==1] Share WebDec 16, 2024 · There are much more efficient ways of finding duplicates in list in python (yours is O(n^2)), and its probably just better using numpy library to do it: import numpy …

Python: count repeated elements in the list - Stack Overflow

WebNov 1, 2011 · It turns out that, if the input array doesn't have duplicate elements, all methods are more or less equally fast, independently of whether the input data is a Python list or a NumPy array. If the input array is large, but contains just one unique element, then the set, dict and np.unique methods are costant-time if the input data is a list. free screen reader app

Get Number of Duplicates in List in Python (Example Code)

WebJan 18, 2014 · As per the str.index docs, signature looks like this. str.index(sub[, start[, end]]) The second parameter is the starting index to search from. So you can pass the index which you got for the first item + 1, to get the next index. WebWith most optimize way with respect to time and space complexity: Step-1: Start travelling the original array from last, Step-2: Once you find the given element. Step-3: Return the index = l - i -1; where l = total length of the array, i = index of the element in step-2. – ArunDhwaj IIITH. Sep 4, 2024 at 17:37. WebJan 3, 2016 · Use enumerate to keep track of the index and a set to keep track of element seen: l = [1, 1, 2, 3] inds = [] seen = set () for i, ele in enumerate (l): if ele not in seen: inds.append (i) seen.add (ele) If you want both: inds = [] seen = set () for i, ele in enumerate (l): if ele not in seen: inds.append ( (i,ele)) seen.add (ele) farms for sale brown county wi

Index of duplicates items in a python list - Stack Overflow

Repeat Elements of a List in Python - PythonForBeginners.com

WebJul 31, 2011 · last_occurence=len(yourlist)-yourlist[::-1].index(element)-1 just easy as that.no need to import or create a function. Share. Improve this answer. Follow answered Apr 13, 2024 at 10:09. Prabu M ... Find last index of element in list with duplicate elements python. 0. index() of last occurrence in list in python. 0. WebHow to count the number of repeated items in a list in Python - Python programming example code - Python programming tutorial - Actionable Python programming code. … free screen readers ukWebOct 12, 2024 · How can I find all the indexes of a recurring item? For Example: list = ['A', 'A', 'B', 'A', 'B', 'B', 'A'] I want to return all occurrences of 'B', so it'd return: indexes = [2, 4, 5] python python-3.x list Share Improve this question Follow edited Apr 18, 2024 at 15:56 Tomerikoo 17.9k 16 45 60 asked Oct 12, 2024 at 5:22 desiigner 79 1 3 10 1 farms for sale by owner in nc

"WebApr 23, 2014 · Using a dictionary to count the items in a list (8 answers) Closed 6 months ago. I am new to Python. I am trying to find a simple way of getting a count of the number of elements repeated in a list e.g. MyList = ["a", "b", "a", "c", "c", "a", "c"] Output: a: 3 b: 1 c: 3 python python-2.7 Share Follow edited Feb 24, 2024 at 8:01 galoget 712 9 15 " - Get index of repeated elements in list python

Get index of repeated elements in list python

python - Pandas: Get duplicated indexes - Stack Overflow

WebHow to count the number of repeated items in a list in Python - Python programming example code - Python programming tutorial - Actionable Python programming code. Data Hacks. Menu. Home; R Programming; ... Accessing Last Element Index of pandas DataFrame in Python (4 Examples) WebFind an index of duplicate elements in list Python Example Simple example code. a = [1, 2, 3, 2, 1, 5, 6, 5, 5, 5] res = [idx for idx, item in enumerate (a) if item in a [:idx]] print (res) Output: Another example using collections You have …

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WebMar 31, 2024 · This program uses the numpy library to convert a given list into an array, finds the indices of the given value in the array, and converts the resulting numpy array back to a list. Finally, it prints the list of indices. Python3 import numpy as np test_list = [1, 3, 4, 3, 6, 7] test_array = np.array (test_list) WebAug 17, 2024 · Example 3: Working of the index () With two Parameters only. In this example, we will see when we pass two arguments in the index function, the first argument is treated as the element to be searched and the second argument is the index from where the searching begins. list_name.index (element, start) Python3. list1 = [6, 8, 5, 6, 1, 2]

WebOct 7, 2008 · @stefanct this likely does double the complexity, I believe the in operator on a list has linear runtime. @ApproachingDarknessFish stated it would iterate twice which answers your question, and is right in saying that doubling the linear complexity is … WebDec 17, 2024 · Python is a great language for doing data analysis, primarily because of the fantastic ecosystem of data-centric python packages. Pandas is one of those packages and makes importing and analyzing data much easier.. Pandas Index.get_duplicates() function extract duplicated index elements. This function returns a sorted list of index elements …

WebDec 10, 2024 · You can use enumerate and check the next index in the list. If an element is not equal to the element in the next index, it is the last duplicate: lst = [1, 1, 1, 2, 2, 3, 3, 4, 5] result = [i for i, x in enumerate (lst) if i == len (lst) - 1 or x != lst [i + 1]] print (result) # [2, 4, 6, 7, 8] Share Improve this answer Follow WebFeb 8, 2024 · To repeat the elements in a list in python, we insert the existing elements of a list to the same list. In this way, the elements in a list get repeated. For instance, If we …

WebAug 22, 2024 · How do I get the index of a duplicated string in a list? Traversing through the length of the list so that we can keep a track of each index and print the index. …

WebJun 15, 2014 · How do I repeat each element of a list n times and form a new list? For example: x = [1,2,3,4] n = 3 x1 = [1,1,1,2,2,2,3,3,3,4,4,4] x * n doesn't work for i in x [i]: x1 = n * x [i] There must be a simple and smart way. python Share Improve this question Follow edited Nov 12, 2024 at 11:01 johan 1,624 2 13 30 asked Jun 14, 2014 at 23:06 free screen reader for macWebIndex: "Return the index in the list of the first item whose value is x." a simple solution would be: for i in range (len (top)): if top [i] == 3: print ('recommendation found at: ' + str (i)) Share Improve this answer Follow answered Apr 9, 2016 at 17:03 Maximilian Peters 29.6k 12 83 96 Add a comment Not the answer you're looking for? farms for sale by owner nswWebJul 11, 2024 · Teams. Q&A for work. Connect and share knowledge within a single location that is structured and easy to search. Learn more about Teams farms for sale by owner in oklahomaWebNov 14, 2024 · Using generator expressions and comprehensions this is pretty straightforward. First let's get all values that appear more than once in a set. x = [1.2, 2.4, 3.1, 4.0, 5.6, 6.5, 1.2, 3.1, 8.1, 23.6, 29.3] multiples = set (a for a in set (x) if x.count (a) > 1) Now, to get the indexes, we can use enumerate and a list comprehension to only ... free screen reader for powerpointWebAug 26, 2024 · While working with Python list, sometimes, we require to check for duplicates and may also sometimes require to track their indices. This kind of … free screen reader software for blindWebMar 23, 2012 · Then it goes to the next element 31, with index 1, and checks if element 31 is present in the input_list[2:] (i.e., from index 2 till end of list), Because 31 is present in input_list[2:], it will return 31. similarly it goes through all the elements in the list, and will return only the repeated/duplicate elements into a list. free screen recorder 10.3.0WebAnd some of the indexes have duplicate values in the 9th column (the type of DNA repetitive element in this location), and I want to know what are the different types of repetitive elements for individual locations (each index = a genome location). I'm guessing this will require some kind of groupby and hopefully some groupby ninja can help me out. farms for sale by owner in kentucky