combinations

问题 I need a predicate to return a list with all combinations of the input list, and the list result size is in the second param, the predicate would be like this permutInListN( +inputList, +lengthListResult, -ListResult), example: permutInListN([1,2,3],2,L). ? L=[1,2]. ? L=[2,1]. ? L=[1,3]. ? L=[3,1]. ? L=[2,3]. ? L=[3,2]. Combinations of [1,2,3] in a list L with length 2 . with no repetitions maybe using setoff. this is my code but it doesn't work at all , no generate all solutions

问题 This questions was asked previously but only for vectors with non-repeating elements. I was not able to find an easy solution to get all combinations from a vector with repeating elements. To illustrate I listed an example below. x <- c('red', 'blue', 'green', 'red', 'green', 'red') Vector x has 3 repeating elements for 'red' and 2 for 'green'. The expected outcome for all unique combinations would be like this. # unique combinations with one element 'red' 'blue' 'green' # unique combination

问题 I have a 4 collections. { A1, A2, A3, ...} { B1, B1, B3, ...} { C1, C2, C3, ...} { D1, D2, D3, ...} I need to find all of the possible combinations using the following rules: 1 item from the first and fourth collections 2 items from the second collection 3 items from the third Example combinations: {A1, B1, B2, C1, C2, C3, D1} {A2, B1, B2, C1, C2, C3, D1} 回答1: Visual Studio was taking too long to load, so I did it in JavaScript since I could test in my console. This will print out all the

问题 I have a search result from two way flight. So, there are two lists that contain the departure flights and arrival flights such as: The departure flights list has 20 flights. The arrival flights list has 30 flights So, I will have 600 (20*30) combination between departure flight and arrival flight. I will call the combination list is the result list However, I just want to select a limitation from 600 combination. For instance, I will select the best of 100 flight combination. The criteria to

问题 I am trying to find all combinations of subsets of from a list, where each element is used only once. To clarify what I mean, given an example list of: [1, 2, 3, 4] I can generate, the following combinations: [(1), (2), (3), (1, 2), (1, 3), (2, 3), (1, 2, 3)] (this should be exhaustive!) Then I can generate combinations of these combinations: [[(1), (2), (3)], [(1, 2), (3)], [(1, 3), (2)], [(1), (2, 3)],[(1, 2, 3)],... (for many)] The main point is that I am only allowed to use each element

问题 I am looking for an efficient way to generate all possible combinations within a certain big range using numpy or any faster method. I tried: from numpy import * from itertools import * dt=dtype('i,i,i,i,i,i') fromiter(combinations(range(10000000),6), dtype=dt, count=-1) but I get a memory error, and even if it worked it will likely take forever to complete. I am looking for combinations that dont repeat. For example, if I needed all 3 number combinations in range(1,5) I will get (1, 2, 3),

问题 I'm doing a brute-force approach to trying to find the combination to an extension to a puzzle. I am trying to get a large number of combinations and then test each combination to see if they fit certain criteria. I generate the combinations using Python's excellent itertools, essentially this gives me an iterator I can go over and test each one. This returns quickly and gives me 91390 combinations to check: itertools.combinations(range(1, 40), 4) This takes a couple of minutes and give me

问题 I have a pandas data frame having 4 rows: df: col1 col2 col3 col4 A1 A2 A3 A4 B1 B2 B3 B4 C1 C2 C3 C4 D1 D2 D3 D4 How do i find all possible combinations of selecting two rows of this data frame. In this case I can choose 2 rows from 4 rows in 4C2 = 6 possible ways df1: col1 col2 col3 col4 A1 A2 A3 A4 B1 B2 B3 B4 df2: col1 col2 col3 col4 A1 A2 A3 A4 C1 C2 C3 C4 df3: col1 col2 col3 col4 A1 A2 A3 A4 D1 D2 D3 D4 and so on..... 回答1: First, you need to find all the combinations using itertools and

问题 There is this great post https://stackoverflow.com/a/3143594/6589735 outlining an algorithm of ranking/unranking combinations. Also, there are concrete implementations in C++, e.g. here https://people.sc.fsu.edu/~jburkardt/cpp_src/combo/combo.cpp I am in need of a very fast implementation in C++, that does rank/unrank combinations encoded as unsigned long long on a x64 Haswell CPU. My attempt is in great need of improvement. unsigned long long rank(unsigned long long comb, int card) {

问题 I'm using this code to bind keyboard keys to custom actions without using the KeyListener : Action left = new AbstractAction() { @Override public void actionPerformed(ActionEvent e) { System.out.println("pressed left key"); } }; Action right = new AbstractAction() { @Override public void actionPerformed(ActionEvent e) { System.out.println("pressed right key"); } }; Action space = new AbstractAction() { @Override public void actionPerformed(ActionEvent e) { System.out.println("pressed space