Python list of dictionaries remove duplicates based on key
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Then, add these strings to a set. Apr 13, 2023 · Then, for each dictionary in both lists, create a new dictionary using dict comprehension where the keys are taken from the set created in step 1 and the values are obtained by checking if the key is present in the dictionary and getting the corresponding value. def func(dic): dic_to_compare = {k: v for k, v in dic. But the main and notable drawback of this approach is that the ordering of the element is lost in this particular method. Share Improve this answer Mar 21, 2017 · Making statements based on opinion; back them up with references or personal experience. For example: v1 = [dict(t) for t in set([tuple(d. 2 that I am attempting to "deduplicate". Sep 11, 2023 · The function ultimately returns a new list containing only unique dictionaries. Sometimes, the same article "title" repeats across dictionaries. Method 1: Using a Loop to Create a Unique List: Feb 22, 2024 · The code utilizes dict. A pair of braces creates an empty dictionary: {} . 6. Use the value of each id property as a key and the dictionary as a value. If you want a list back then just take filtered_dict. Counter(f. Apr 18, 2019 · If any value of url is duplicated - exclude it from dict. ) So, what do you think now is the most elegant and most “pythonic” way to implement this problem in Oct 17, 2021 · Need to check if a key exists in a Python dictionary? Check out this tutorial, which teaches you five different ways of seeing if a key exists in a Python dictionary, including how to return a default value. One simple approach would be to create a reverse dictionary using the concatenation of the string data in each inner dictionary as a key. def remove_duplicates(myList): return list (set(myList)) From looking at your code it seems that you are not bothered about the ordering of elements and concerned only about the uniqueness. Feb 11, 2020 · I want to reduce this list of dictionaries to take the most current record of the duplicates, where duplicates are determined by same project_name and same feature_group_name. e) [1] == [3,4] which will not be true. This usually means that they have to be immutable. You can still use a set for duplicate detection, you just need to convert the dictionary into something hashable such as a tuple. Python - remove duplicate of dict that contains list of lists. Lists are created using square brackets: Sep 19, 2021 · Now that you have an understanding of what dictionaries are, let’s see how we can use Python to remove a key from a dictionary. I want to keep pair of devices. Just deserialize the json serialize it again and the dupes will be gone. Share Improve this answer Mar 27, 2012 · I'll assume that two dictionaries with equivalent type and name keys are identical, and that you want the relevance values to be merged into a list. So if there the same key with different values inside I would like to not remove it, but if there is a complete copy then remove it. stdout, indent=2) Dec 21, 2021 · So in the example the first and third dictionary are the same. defaultdict(list) >>> for key, inner_d in d. seenKeys = set() # List to store dictionaries without duplicates. 3) Example 2: Detect & Eliminate Duplicates in List of Feb 26, 2019 · Essentially, I have a list of dictionaries, and I want to remove duplicates from the list based on the unique combination of two (or more) keys within each dictionary. Sets, as you're probably aware, will also remove duplicates. 'path1' is related to 'file1' and 'path2' is related to 'file2' as is the 'f' in key2 for both cases. Use Python . A better-rounded approach that works regardless of the order of the input would be to build a dict that maps f_ids to respective dicts, but convert the record_id value to a list when there are multiple records with the same f_ids: . You could create your own dict object with a special hash, but this seems easier. This would work for strings too, just returning individual characters, which is not what you want. dump(seen. I've seen numerous similar questions, but the answers only work with simple dictionaries in a list, not nested dictionaries. Loop through the key-value pairs in the original dictionary (test_dict). >>> reverse_d = collections. for d in b: print d['id'] for desc in d['desc']: print desc. This tutorial will show you how to detect and eliminate duplicates in a list of dictionaries in the Python Programming language. EDIT2: Maybe I was a bit confusing. This dictionary will hold one set (for fast lookup) for each key of the original dict. . Try this and post the results. 6+ (and all other Python implementations starting with Python 3. We can find the dictionary with the required key using a loop and then remove it using the remove () method. value_occurrences = collections. Basically, get key from dictionary with one element. Assuming that all dictionaries contain the same keys, you could also convert it to a pandas DataFrame, delete the column and convert it back to a list of dictionaries: import pandas as pd. Within the data structure, bunch dict are duplicate. May 31, 2017 at 9:09. – linus. 6, dictionaries keep insertion order , so dict. iteritems(): Jan 10, 2014 · So I have a neat list of dictionaries sorted by Matchcode. Now I just need to iterate over the list, accessing the list[dictionary][key] and deleting duplicates when two key values match. items() may have different key-ordering, even if the keys are identical, so I've introduced the canonical_dict function to address this concern. In such a case, a set () could be a better data structure. This is particularly useful for Pydantic which doesn't support hashable types by default: { row. So, I have something like: a=[{'id': 1, 'name': 'pa May 30, 2024 · If you are in a hurry, below are some quick examples of how to remove multiple keys from the Dictionary. W3Schools offers free online tutorials, references and exercises in all the major languages of the web. Given a key, I want to remove all the dictionaries from the list except the last one that has duplicate value for that key. values(), sys. Finally, create a set, to remove duplicates. no title repeats across the dictionaries. def removeDuplicatesByKey(dictList, key): # Set to track keys we've seen. items() and d2. 2) Example 1: Detect & Eliminate Duplicates in List of Dictionaries Using for Loop & set () Function. # Quick examples of remove multiple keys from dictionary. The Python . Then v[[*v][0]] gets value associated with this key. 0. 2. Exchange keys and values again. The below dict comprehension will create a new dict from the original one without any duplicate values: samples_antibiotics = {k: list(set(v)) for k, v in samples_antibiotics_with_duplicates. Jan 31, 2019 · Need to remove duplicates from a list of dictionaries and alter data for the remaining duplicate (python) 4 Remove duplicates from a list of dictionaries when only one of the key values is different Aug 9, 2012 · As gnibbler points out, d1. I do not want to use a k/v swap since that can not control the key selection. keys_list = ['fee', 'discount', 'course'] for key in keys_list: del my_dict[key] # Example 2: Use pop() & list comprehension to. Feb 21, 2024 · Hello I have bulk of list of dict and would like to remove duplicate dict and value with None. We can use the remove () method of list to remove the dictionary with the required key from the list of dictionaries. Value. lower) Also note that you don't need a lambda function as your key, you can simple use str. I'm still not entirely sure what this means. That is my problem. Aug 4, 2010 · 9: 'a'} I want to remove duplicate values just keep one K/V pair, Regarding the "key" selection of those duplicated values, it may be max or min or by random select one of those duplicated item's key. list objects), then you will have to use a slow approach in which you will basically have to compare every item with every other item in a nested loop. Your dictionaries can be converted to tuples by tuple(d. Expected output: Aug 5, 2019 · I have a list of dictionaries that has some duplicate IDs in and I would like to keep the dictionaries that have a value under rsrp and remove the ones that have 0, but if there is a duplicate that has rsrp of 0 in twice I need to keep it. Removing duplicate dictionaries in list of dicts based on value uniqueness for a given key. Removing repeated dictionaries in a list of dictionaries based on 2 keys. I have a pretty basic (but not quite working) function to dedupe a list of dictionaries from key values by adding the key value to a list for keeping track. values() should give you the output you need. Let’s see the complete example, Copy to clipboard. All of the dictionaries are unique, but there is a specific key I would like to deduplicate on, keeping the dictionary with the most non-null values. Jan 6, 2012 · 6. Each dictionary is guaranteed to have a key called "index", but could have an arbitrary set of keys beyond that. The actual dictionary has many other keys, but what I'm trying to do is to delete all the entries that have the exact same key pair values, except for the date. In this case, what I would expect to get is: 2. Applying that to your generator function: def removeduplicate(it): seen = set() for x in it: Jan 4, 2019 · Related, not exact duplicate as here we only want to consider one key when considering duplicates: Remove duplicate dict in list in Python – jpp Jan 4, 2019 at 13:04 May 2, 2023 · Approach: Using remove () method. items()} The set version of a list (or any container) does not contain any duplicates since sets do not allow any (that is why they require hashable 9. The problem in your code is just to use a function argument name which is not the name of the Aug 17, 2011 · first, I transform the inital dict in a list of tuples, then I put them into a set (that removes duplicates entries), and then back into a dict. S. 1. append(d) Jun 11, 2019 · If you are certain that all the filter dictionary's keys exist in the other dictionaries, you could write the search like this (in other words, absent keys will be considered to match): filterDict = {"name":"Peter"} result = [ d for d in orig_list if {**d,**filterDict} == d ] Nov 10, 2021 · It filter and flattens all the values in the list before the certain key and filters the values not in there. Aug 8, 2018 · Now, I was wondering if there is an efficient way to remove duplicates from this list. BulkData [ {& Jun 30, 2020 · And also the statement (if value not in newdict[key]), here value is a list and newdict[key] will also be a list(if you solved the above mentioned problem), so you're comparing two lists. count() and . delist = [] for r in rs: if r['key'] not in delist: delist. lower method. union(*results[env]. There's another possible solution here. pop():. Since python 3. sort() Loop through the (sorted) list, removing unique objects as we go. from itertools import * arr = [ {'name': 'saeed1-gr1', 'id': 1 1 day ago · It is best to think of a dictionary as a set of key: value pairs, with the requirement that the keys are unique (within one dictionary). append(r['key']) else: rs. If you have to deal with items that are not hashable (e. Key, pair => pair. values(). In general if you want to find duplicates in a list of dictionaries you should categorize your dictionaries in a way that duplicate ones stay in same groups. The dictionaries will always have the same keys. Universal approach to filter the list of dictionaries based on key-value pairs. title : row for row in rows }. So say you have the above data in a dictionary, d: >>> import collections. Common use cases where duplicate removal is crucial. Actually in reality there are several keys more, but this is my minimal example. Suppose I have the following list of dictionaries: May 17, 2021 · remove duplicates dictionary from a list based on a specific key and value 0 How to remove duplicate values from a list of Python dictionaries where order is preserved? Jul 17, 2020 · I have a list of dictionaries where each dictionary is information about an article. Here is an overview: 1) Create Demo List of Dictionaries. items()) for d in v0])] This would work if the dictionaries were not nested, but because they are, I get the Jul 5, 2022 · Use Built-in List Methods to Remove Duplicates. Value); This way you will remove the duplicate only on one property of the object. append(d) else: duplicateValues. Sep 10, 2015 · In addition to the answer of Jon Skeet , if your value is an intern object you can use : var uniqueValues = myDict. You can use the Python list methods . May 31, 2017 · 1. For that purpose you need to categorize based on dict items. How to Remove Duplicates from a List in Python. Use another dictionary (or defaultdict) to keep track of what values you have already seen for what keys. . i need to remove the duplicates if the values of both those keys are same. Jan 17, 2018 · To delete dictionaries with duplicate values for keys in two dictionary lists Hot Network Questions Powershell - Trying to streamline a Get-Service Command Jun 6, 2017 · 3. items() if value_occurences[value] == 1} To find how many were removed, just subtract the new dict's size from the old. Oct 21, 2012 · 3. values()) then filter out the ones that appear more than once: filtered_dict = {key: value for key, value in f. And now the solution giving you a list of dicts of lists: Mar 2, 2022 · Python - Remove duplicate key from a list of dictionaries. values() returns a view object that displays a list of all the values in the dictionary - here a list of whole unique (by id) dicts. The non-index keys will never overlap across lists. com) task 789 with 2 dict in results (exclude site. Summary/Discussion Feb 18, 2019 · As you can observe in the list dictionary in my_dict list, the duplicate dict values are removed or filtered out from the list and only the first entry for that dict instance is taken in the filtered output. If it is, go to step 3. Mar 14, 2015 · 1. Understanding the Significance of Removing Duplicates: Importance of maintaining unique elements in certain scenarios. pop() method works Feb 3, 2012 · There's no need for defaultdicts or sets here. ruledict_list can be the example data in your question. First()) . DataFrame(list_of_dicts) Count the values: import collections. values() method to only get the unique dictionaries. Feb 26, 2013 · 3. 4. Use the list() class to convert the result to a list. I have found several solutions to delete every duplicate. Aug 18, 2021 · Tried flicking with { each[''] : each for each in te }. Sets are unique Python data structures that are generated using the curly braces By default, keys in dictionaries are unique, so if the dict with the same id is being added to this new dictionary, it overwrites previous dict with the same id. Mar 25, 2021 · I have a list of dictionaries, and each dictionary can have any key - value pairs. Like : sel_list = [{'a': 8}, {'b': 9}] Nov 11, 2020 · filtered_dict = {(d['id'], d['updated_at']): d for d in list_of_dicts} Since you mention no preference in your question, this will probably take the last duplicate. Property) . count() method returns the number of times value occurs in list. For example, imagine the following two lists: Nov 27, 2015 · 1. compiled_list = list() compiled_list_keys = list() duplicates_list = list() for attribute in attribute_list: for k, v in attribute Nov 6, 2012 · 0. This way you can do. pop() method is a very useful method that allows us to get a dictionary item and remove its key from the dictionary. You can't have a dict with duplicate keys for definition! Instead you can use a single key and, as the value, a list of elements that had that key. You can then use a simple loop or a tricky comprehension like the following (making use of the workings of the or operator): Apr 27, 2023 · Create an empty list called seen_values to keep track of the values that have already been seen. – With the syntax list. Is that enough? There are no duplicates in dicts. I am only looking at one key-value. For example, I have the following list of dictionaries: See full list on geeksforgeeks. So the count corresponding to repeating items will be greater than 1. test_list = [1, 5, 3, 6, 3, 5, 6, 1] print ("The original list is : ". 5. The loop will also remove one of each duplicate object, but that doesn't Mar 14, 2017 · Python - remove duplicate item from list of dictionaries based on dictionary value 1 Removing duplicate dictionaries in list of dicts based on value uniqueness for a given key Apr 10, 2021 · Python - remove duplicate item from list of dictionaries based on dictionary value 3 Python: Update the dict[key] values list only with values not already in list I have an extension question to remove dictionary from list, except that I have a list of dictionary keys I would like to remove from the list. items()) where d is a dictionary. 1: 'a', 2: 'a', For non-hashable types you can use a dictionary comprehension to remove duplicate objects based on a field in all objects. Oct 17, 2021 · Need to check if a key exists in a Python dictionary? Check out this tutorial, which teaches you five different ways of seeing if a key exists in a Python dictionary, including how to return a default value. Lists are used to store multiple items in a single variable. org Apr 9, 2024 · To remove the duplicates from a list of dictionaries: Use a dict comprehension to iterate over the list. As result: task 123 with 3 dicts in results task 456 with 1 dict in results (exclude site. fromkeys() to construct a new dictionary where the keys are extracted from the ‘id’ values of each item, and the last instance of each key becomes the value in the new dictionary. Now, since for dictionaries Order is not an important factor you need to use a container that is both hashable and doesn't keep Jul 10, 2020 · However, I would like to be able to remove duplicates based on the key and all values associated within that dictionary. Which gets used in the script just below on two lists of dictionaries: Aug 10, 2018 · Below is the code that I have so far, this gets me as far as having two dictionaries but 1) I think this is horribly inefficent and 2) I can't work out how to remove the first instance of a duplicate dictionary. 3. if not any(d[k] in seen[k] for k in d): filt_dic. Sep 12, 2022 · In this tutorial, we'll learn the different methods for removing duplicates from a Python List. Because sets in Python cannot have Dec 22, 2014 · Given n lists with m dictionaries as their elements, I would like to produce a new list, with a joined set of dictionaries. Lists are one of 4 built-in data types in Python used to store collections of data, the other 3 are Tuple, Set, and Dictionary, all with different qualities and usage. Python3. Use Python Sets to Remove Duplicates from a List. list_of_dicts = [{'mykey1':'myvalue1', 'mykey2':'myvalue2'}, {'mykey1':'myvalue1a', 'mykey2':'myvalue2a'}] df = pd. Apr 21, 2024 · Here’s how you can use a set to remove exact match duplicates from a JSON array: First, convert your JSON objects into a string format since sets cannot directly handle dictionaries. Sets are unique Python data structures that are generated using the curly braces Oct 27, 2013 · Convert this list of dict to a dict of dict will remove the duplicate, like so: r = dict([(user['name'], user) for user in JSON]) In r you will only find one record of fred and peter each. Aug 11, 2023 · This is the most popular way by which the duplicates are removed from the list is set () method. Summarize the best running score in a dictionary and convert the result back into a list: Delete duplicate value-items from multiple keys in python dictionary and append to a new dictioanry 0 append all values in a dict if all elements exists and remove duplicates Mar 2, 2021 · Python Remove duplicates from list of dictionaries based on a value. Nov 13, 2009 · Now, create a list of these objects, and sort it. P. """Func to be used for map/filter function, returned func will take dict values from kwargs keys and compare resulted dict with kwargs""". May 3, 2020 · A piece of advice: given your final data structure, I wonder if you may be better off now representing this final data as a dictionary - with the IDs as keys since these are now unique. Aug 8, 2018 · I want to remove duplicate dictionaries and if more than one dictionaries have same key but different values then choose that dictionary with higher value. Then at the end, you can convert this intermediate dict into a list of dicts. Using the del keyword. We use the del keyword to delete objects from a list with their index position. I renamed your dict to dct so it doesn't override the function name Nov 1, 2011 · Finally note that both the set as well as the OrderedDict/dict solutions require your items to be hashable. pop() to Delete a Key from a Dictionary. So you can follow these steps: See if the current element's key (of your initial set) is in the final dict. Apr 8, 2024 · I added comments to each part, and I also added another case where more than 2 items are similar. 7+), dictionaries are ordered, so the way to remove duplicates from an iterable while keeping it in the original order is: Sep 24, 2021 · @U12-Forward's answer works only if the input is pre-sorted, with records of the same f_ids already grouped together. Use the dict. com) Desired output should looks like: "task_id":123, To delete a key regardless of whether it is in the dictionary, use the two-argument form of dict. Instead, you should iterate every value in any one of the list and compare it with another list. Create a new dictionary called result_dict to store the non-duplicate values. That is, to delete all duplicates (which are not really exact duplicates as only the date varies). Placing a comma-separated list of key:value pairs within the braces adds initial key:value pairs to the dictionary; this is also the way dictionaries are Feb 8, 2015 · Exchange keys and values; duplicated key-value pairs will be removed as a side effect (because dictionary does not allow duplicated keys). It sounds like you're saying they will always be sorted by the same key you want to use to uniquify. The remove () method removes the first occurrence of the specified element in the list. By then taking the values of this dictionary, we achieve a list of unique dictionaries by ‘id’. May 21, 2019 · It unpacks keys found in dictionary v into a list and then picks first key. g. Then later you could average them, or whatever. i. # Example 1: Remove multiple keys using del keyword. It is better to keep the "desc" values as lists everywhere even if they contain a single element only. load(sys. remove() to remove duplicate items. You can just use dirt simple dicts and lists. May 13, 2020 · You should keep a set of seen values for key "one". Jan 9, 2014 · I don't care about order, I just want the set of all elements. Finally, convert the strings back into JSON objects. Mar 15, 2019 · duplicateValues = [] for d in dataList: if key_counts[d['Key']] == 1: uniqueValues. stdin, object_pairs_hook=OrderedDict) seen = OrderedDict() for d in L: oid = d["obj_id"] if oid not in seen: seen[oid] = d json. The impact of duplicates on data analysis and processing. values() Dec 16, 2021 · We then filter our dictionary to remove any key:value pairs where the key only exists a single time; In the next section, you’ll learn how to remove duplicates from a Python list. It does this by first creating an OrderedDict called odict, where the keys are tuples containing the items of the dictionaries in ini_dict, and the values are Oct 15, 2021 · I'm trying to get a simple Python code to merge a list of dictionaries into a condensed list as I have lots of duplicates atm. Removing duplicates in a Python list is made easy by using the set() function. Apr 12, 2016 · Since results[env] is a dictionary you can create a set of union values instead of flattening the values then sort the result: >>> sorted(set(). For example, I have the following list of dictionaries: Jan 25, 2024 · Brief overview of duplicate elements in lists. e. answered Oct 27, 2013 at 5:30. Update dict with key. ) Delete this dict element or elements (based on the found keys) from myDict (For more information, see Delete an element from a dictionary. values(), but to no avail. Yes, a dictionary has to have unique, hashable keys, so you'll need to look at non-keyed collections such as lists or tuples. Select(group => group. append(d) Don't be tempted to skip the counting loop, while you can count d['Key'] values in a for d in dataList: loop too, you'd repeat that count for duplicate keys several times, and you would have to loop over all of dataList May 23, 2018 · I have a list of dictionaries in Python 3. if you execute this as a dictionary code it will overwrite the duplicates. From this: [ { "module": "RECEIPT BISCUITS&qu Sep 21, 2019 · Loop through all entries in list_of_unique_dicts, if the key for this entry doesn't exist in the intermediate dict, add it, otherwise update the value in the intermediate dict. GroupBy(pair => pair. ToDictionary(pair => pair. I want to remove these duplicate dictionaries so that each article in the list of dictionaries is unique by title i. So the result should be something like: r = [{'id': 'scissor'}, {'id': 'cloth'}] I tried using frozenset but the dictionary type cannot be hashed. items() if k in kwargs} Apr 27, 2023 · This code converts a nested dictionary ini_dict into another dictionary called result, with the original keys as the keys and the dictionaries as the values where duplicates are removed. 1 In CPython 3. Is there an efficient way to do this from any structures in the python library? Mar 24, 2015 · Get a list of all keys of a certain value in myDict (See for instance get key by value in dictionary. rules = [rule(**r) for r in ruledict_list] rules. I have Jun 13, 2022 · Python - Remove duplicate key from a list of dictionaries. uniqueList = [] for d in dictList: May 21, 2018 · I have a list of dictionaries in Python 3. I have tried looking at Find duplicates in python list of dictionaries and python list of dictionaries find duplicates based on value, but I can't find the exact answer. my_dict. values()), key=str. This would allow for more convenient data access. How do I go about doing Jan 15, 2015 · I don't want to delete every duplicate in every key. pop('key', None) This will return my_dict[key] if key exists in the dictionary, and None otherwise. If any dictionary does not have specified key, it should be in the final resultset. remove(r) return rs. This process automatically removes any duplicates. Anthony Kong. – DatHydroGuy. Take value "a" for example. count (value), the . For each key-value pair, check if the value is already in seen_values. We use this method when the size of the list is small and there aren't many duplicate elements. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more. Jun 12, 2013 · Here's an implementation that preserves order of input json objects and keeps the first occurrence of objects with the same id: import json import sys from collections import OrderedDict L = json. Jun 16, 2022 · Upon encountering a duplicate item, the dict comprehension will overwrite the previous item with the duplicate one, but that doesn't make any material difference because both items are identical. aheyjzlomfwrbvqbxsph