Sort a List of Integers 5 1 List<Integer> numbers = Arrays.asList(6, 2, 1, 4, 9); 2 System.out.println(numbers); 3 4 numbers.sort(Comparator.naturalOrder()); 5 System.out.println(numbers);. You can use this generic comparator to sort list based on the the other list. Short story taking place on a toroidal planet or moon involving flying. All the elements in the list must implement Comparable interface, otherwise IllegalArgumentException is thrown. Then, yep, you need to loop through them and sort the competitors. Given parallel lists, how can I sort one while permuting (rearranging) the other in the same way? When we try to use sort over a zip object. Most of the following examples will use lists but the same concept can be applied for arrays. Linear regulator thermal information missing in datasheet, How to tell which packages are held back due to phased updates. Java LinkedList Sort Example - Java Code Examples I am also wandering if there is a better way to do that. Note that you can shorten this to a one-liner if you care to: As Wenmin Mu and Jack Peng have pointed out, this assumes that the values in X are all distinct. then the question should be 'How to sort a dictionary? Surly Straggler vs. other types of steel frames. Now it actually works. If you try your proposed code, it would give something like this: Person{name=Giant L2, age=100} Person{name=Derp L1, age=50} Person{name=John L2, age=50} Person{name=Menard L1, age=44} Person{name=Lili L1, age=44} Person{name=Lili L2, age=44} Person{name=Menard L2, age=44} Person{name=Bob L1, age=22} Person{name=Alec L1, age=21} Person{name=Herp L1, age=21} Person{name=Alec L2, age=21} Person{name=Herp L2, age=21} Person{name=Alice L1, age=12} Person{name=Little L2, age=5} And it's not what I'm looking for. We've sorted Comparable integers and Strings, in ascending and descending order, as well as used a built-in Comparator for custom objects. You should instead use [x for (y,x) in sorted(zip(Y,X), key=lambda pair: pair[0])]. Let's say we have the following code: Let's sort them by age, first. I think that the title of the original question is not accurate. A:[c,b,a] My question is how to call compare method of factoryPriceComparator to sort factories? All of them simply return a comparator, with the passed function as the sorting key. To learn more, see our tips on writing great answers. What sort of strategies would a medieval military use against a fantasy giant? The nature of simulating nature: A Q&A with IBM Quantum researcher Dr. Jamie We've added a "Necessary cookies only" option to the cookie consent popup, The most efficient way to merge two lists in Java, Java merge sort implementation efficiency. This tutorial covered sorting of HashMap according to Value. Key and Value can be of different types (eg - String, Integer). We are sorting the names according to firstName, we can also use lastName to sort. There are two simple ways to do this - supply a Comparator, and switch the order, which we'll cover in a later section, or simply use Collections.reverseOrder() in the sorted() call: Though, we don't always just sort integers. Sorting List and Stream on Multiple Fields Java 8 Example Note: the key=operator.itemgetter(1) solves the duplicate issue, zip is not subscriptable you must actually use, If there is more than one matching it gets the first, This does not solve the OPs question. (This is a very old answer!). Output: Lets see another example where we will sort a list of custom objects. To learn more about comparator, read this tutorial. Guide to Java 8 Collectors: groupingByConcurrent(), Java 8 - Difference Between map() and flatMap(), Java: Finding Duplicate Elements in a Stream, Java - Filter a Stream with Lambda Expressions, Guide to Java 8 Collectors: averagingDouble(), averagingLong() and averagingInt(), Make Clarity from Data - Quickly Learn Data Visualization with Python, // Constructor, getters, setters and toString(), Sorting a List of Integers with Stream.sorted(), Sorting a List of Integers in Descending Order with Stream.sorted(), Sorting a List of Strings with Stream.sorted(), Sorting Custom Objects with Stream.sorted(Comparator Sorting list based on values from another list - Stack Overflow It is stable for an ordered stream. As for won't work..that's right because he posted the wrong question in the title when he talked about lists. The solution below is simple and does not require any imports. Oh, ignore, I can do sorted(zip(Index,X,Y,Z)) too. 1. Make the head as the current node and create another node index for later use. Using Kolmogorov complexity to measure difficulty of problems? If you have 2 lists of identical number of items and where every item in list 1 is related to list 2 in the same order (e.g a = 0 , b = 1, etc.) Not the answer you're looking for? Overview Filtering a Collection by a List is a common business logic scenario. Its likely the second set is a subset of the first. QED. java - Sorting a list and another list inside each item - Code Review String values require a comparator for sorting. Why are physically impossible and logically impossible concepts considered separate in terms of probability? you can leverage that solution directly in your existing df. Unsubscribe at any time. NULL). Why are Suriname, Belize, and Guinea-Bissau classified as "Small Island Developing States"? Overview. Key Selector Variant. Follow Up: struct sockaddr storage initialization by network format-string. How To Install Grails on an Ubuntu 12.04 VPS, Simple and reliable cloud website hosting, New! Connect and share knowledge within a single location that is structured and easy to search. Best answer! The solution assumes that all the objects in the list to sort have distinct keys. Asking for help, clarification, or responding to other answers. This will provide a quick and easy lookup. Why do academics stay as adjuncts for years rather than move around? Warning: If you run it with empty lists it crashes. Using Comparator. How to make it come last.? Sort a List of Objects by Field in Java - Hire Amir To get a value from the HashMap, we use the key corresponding to that entry. Once, we have sorted the list, we build the HashMap based on this sorted list. Sorting values of a dictionary based on a list. The solution here is not to make your class implements Comparator and define a custom comparator class, like. How is an ETF fee calculated in a trade that ends in less than a year? This work is licensed under a Creative Commons Attribution-NonCommercial- ShareAlike 4.0 International License. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. zip, sort by the second column, return the first column. How Intuit democratizes AI development across teams through reusability. In addition, the proposed solution won't work for the initial question as the lists X and Y contain different entries. @RichieV I recommend using Quicksort or an in-place merge sort implementation. QED. The naive implementation that brute force searches listB would not be the best performance-wise, but would be functionally sufficient. We can also pass a Comparator implementation to define the sorting rules. That way, I can sort any list in the same order as the source list. In which case this answer is somewhat valid, but just needs to be the intersection of sets (remove missing elements). I was in a rush. I like having a list of sorted indices. Sort an array according to the order defined by another array using Sorting and Binary Search: The idea is to sort the A1 [] array and then according to A2 [] store the elements. Collections.sort() method is overloaded and we can also provide our own Comparator implementation for sorting rules. This solution is poor when it comes to storage. Python. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. However, some may lead to under-performing solutions if not done properly. Now it produces an iterable object. You are using Python 3. Let's save this result into a sortedList: Here we see that the original list stayed unmodified, but we did save the results of the sorting in a new list, allowing us to use both if we need so later on.