In set theory, the union (denoted by ∪) of a collection of sets is the set of all distinct elements in the collection. It is one of the fundamental operations through which sets can be combined and related to each other. In C++, set_union() constructs a sorted range consisting of all elements present in one or both sorted input ranges.
Questions tagged [set-union]
90 questions
1
vote
3 answers
How to combine values composed of lists with common items in a dictionary using Python?
I have a dictionary that resembles the following:
dict1 = {'key1':['1','2','3'],'key2':['3','4','5'],'key3':['6','7','8']}
I would like to merge all keys that have at least one common element and as a result. For example, the resulting dictionary…
Vince
- 235
- 6
- 19
1
vote
2 answers
union of two default dictionaries
am trying to create a union of two default dictionaries. Here is the code for the method in my class:
def __add__(self,right):
mergedbag = copy.copy(self.bag_value)
for item in right:
if item not in mergedbag:mergedbag[item] = 0
…
BoJaNgLeS
- 61
- 6
1
vote
0 answers
Searching for a fast way to compare two matrices in R
Given two [n,2] matrices I would like to compare them, like in the following example:
library('fastmatch')
Matrix2Curt=cbind(c(1,2,3,4),c(5,6,7,8))
…
mthrun
- 71
- 1
- 6
1
vote
1 answer
How to write a intersection and union methods for sets in Java
I'm new to using sets and for one of the exercise to learn how to use sets, I have been given a template file "SetInt" and a completed test file "TestSetInt". I know that I should use retainAll() and addAll() but the test class has asked me to write…
MOZAKATAK
- 483
- 1
- 7
- 14
1
vote
1 answer
No Overloaded operator= showing in algorithm.cpp
I am working with set_union (included in algorithm.cpp) and sets in the STL library.
My sets hold objects of a custom class Vertex in which I have overloaded the operator=
Here is the Vertex class:
class Vertex {
public:
City city;
bool…
Joe
- 2,386
- 1
- 22
- 33
0
votes
2 answers
using set_union() with a lambda
I would like to use set_union() and just scan the output without having to store it.
Something like this (it doesn't compile using g++12.1.0):
#include
#include
#include
using namespace std;
int main()
{
…
Ludovic Aubert
- 9,534
- 4
- 16
- 28
0
votes
0 answers
Use set union on a SeriesGroupBy
Suppose that I have a dataframe(df) like above, I want to run df.groupby(['id', 'client']) and the apply union on the items column ?
The result should be one row -> id = 1 and client = 70 items= {1,2,3,4,5,6,7}.
I appreciate any help with this!
Dani
- 857
- 1
- 6
- 8
0
votes
2 answers
How to combine items from two ConcurrentBags?
For Lists I could use the Union method:
var finalCollection = new List();
var list1= new List();
var list2 = new List();
finalCollection = list1.Union(list2).ToList();
But when I try to do the same with ConcurrentBags,
var…
KWC
- 109
- 1
- 8
0
votes
2 answers
Priority Queue union, intersection, difference compiling but not returning into output
My program prints the main constructor but is not returning the 3 bottom functions but its compiling.
Where am I going wrong?
import java.util.*;
public class Main {
public static void main(String[] args) {
PriorityQueue queue1 = new…
Luk
- 33
- 5
0
votes
2 answers
How to use set intersection or union on 2D array in ruby?
Say I have a 2D array like so:
[ [0, 1], [2, 3], [0, 4] ]
How can I use intersection or union of those arros above to get the result of:
[[0, 1, 4], [2, 3]]
To explain the above:
The reason for [0, 1, 4] is because 0 is connected to 1 and 4
The…
Jamy
- 115
- 1
- 9
0
votes
1 answer
error when taking the union of two integers which are in a set
I have written the following code
p1=1
p2=2
p3=set(p1).union(set(p2))
p3
In this case I would have expected for p3 to be equal to {1,2}, but when trying to run the program, I obtain:
'int' object is not iterable
How may I fix this?
Is there…
Stiven G
- 215
- 2
- 7
0
votes
1 answer
Syntax of union of several sets
I would like to understand why is this a valid syntax:
common = (set(classes['Biology']) & set(classes['Math']) & set(classes['PE']) & set(classes['Social Sciences']) & set(classes['Chemistry']))
but not this:
common = set(classes['Biology']) &…
boldi
- 83
- 1
- 6
0
votes
3 answers
Merging two three column matrices: uniques in cols 1&2, maximum in col 3
I have two matrices:
a = [ 1 10 20; 2 11 22; 3 12 34; 4 13 12];
b = [ 3 12 1; 4 13 25; 5 14 60; 6 15 9 ];
I want to merge them into a single matrix where the rows with the maximum in column 3 used where columns 1 and 2 are identical, i.e. the…
Tomm
- 2,142
- 1
- 15
- 19
0
votes
1 answer
list of a list in scheme
I have a list that I get from a lambda, and I want to create (and return) a list that contains an element of a list. Scheme doesn't let me do it.
#lang racket
(define omega
(lambda (n)
(if (= n 0) 'Φ
(cons (omega (- n 1)) '(omega (- n…
J. Doe
- 95
- 8
0
votes
1 answer
(PureScript) How to create a Union of two separately defined rows of effects
I'm essentially needing to know how to write a function like this...
joinCommands :: forall e1 e2 e3
. Union e1 e2 e3
=> Eff e1 Unit
-> Eff e2 Unit
-> Eff e3 Unit
joinCommands fn1 fn2 = do
fn1
fn2
Which doesn't work. I get this…
Albtzrly
- 924
- 1
- 6
- 15