How do i insert one value from one array to another array

7 Ansichten (letzte 30 Tage)
I have 2 arrays with coordinates. For example
A = [1,2;2,1;1,1;1,3;3,2]
A = 5×2
1 2 2 1 1 1 1 3 3 2
B = [0.5,0.5;2,2]
B = 2×2
0.5000 0.5000 2.0000 2.0000
I compute for every point in A the nearest Point from B. I use dsearchn
k = dsearchn(B,A)
k = 5×1
2 2 1 2 2
Now I want to give every point in B the next points from A. Making for every point in B a list of nearest points from A. Like point B(2,:) ans = 2 , 2 has the next points A(1,:),A(2,:),A(4,:) and A(5,:). I have no clue how to do it right and efficient.
  2 Kommentare
Rik
Rik am 2 Aug. 2022
What is the actual output in terms of Matlab variables you want?
Lars Urban
Lars Urban am 2 Aug. 2022
I thought about a structure array where it is divided by coordinate of B in x and y and the a list of double from A.x and A.y

Melden Sie sich an, um zu kommentieren.

Akzeptierte Antwort

Bruno Luong
Bruno Luong am 2 Aug. 2022
See if s is what you want or not (not clear for me)
A = [1,2;2,1;1,1;1,3;3,2]
A = 5×2
1 2 2 1 1 1 1 3 3 2
B = [0.5,0.5;2,2]
B = 2×2
0.5000 0.5000 2.0000 2.0000
k = dsearchn(B,A)
k = 5×1
2 2 1 2 2
AA = accumarray(k, (1:size(A,1))', [], @(r) {A(r,:)});
s = struct('B', num2cell(B,2), 'A', AA)
s = 2×1 struct array with fields:
B A
s(1).B
ans = 1×2
0.5000 0.5000
s(1).A
ans = 1×2
1 1
s(2).B
ans = 1×2
2 2
s(2).A
ans = 4×2
1 2 2 1 1 3 3 2
  1 Kommentar
Lars Urban
Lars Urban am 3 Aug. 2022
Yes this is what i want at the end. Sorry for the bad description of my problem. Thank you!

Melden Sie sich an, um zu kommentieren.

Weitere Antworten (1)

David Hill
David Hill am 2 Aug. 2022
Look at pdist2
A = [1,2;2,1;1,1;1,3;3,2] ;
B = [0.5,0.5;2,2];
pdist2(A,B)
ans = 5×2
1.5811 1.0000 1.5811 1.0000 0.7071 1.4142 2.5495 1.4142 2.9155 1.0000
  2 Kommentare
Lars Urban
Lars Urban am 2 Aug. 2022
It would be end in the same problem where i have to sort each point with the closest distance to one point B. I have found w dsearch for each point in A the closest point in B but i want to sum for every point in B their closest points from A.
David Hill
David Hill am 2 Aug. 2022
I don't understand your comment. Each column above gives the distance between each point in B with all the points in A. You could sort each column and then index into A to provide the sorted listing of the closest points of A to each point in B.

Melden Sie sich an, um zu kommentieren.

Kategorien

Mehr zu Matrices and Arrays finden Sie in Help Center und File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by