How can I mix two arrays?
8 visualizzazioni (ultimi 30 giorni)
Mostra commenti meno recenti
Alex Strongholm
il 15 Gen 2015
Modificato: Stephen23
il 18 Gen 2015
Given A=[1 3 5 7 9] and B=[2 4 6 8], how can I create C=[1 2 3 4 5 6 7 8 9]?
0 Commenti
Risposta accettata
Youssef Khmou
il 15 Gen 2015
Modificato: Youssef Khmou
il 15 Gen 2015
This question is general due to the variation of array dimensions, however for a particular case you described, vectors A and B can be mixed by single loop, so the following scheme is valid only when dim(A)=dim(B)+1 as in the example :
A=[1 3 5 7 9];
B=[2 4 6 8];
n=min(length(A),length(B));
C=[];
for t=1:n
C=[C A(t) B(t)];
end
C=[C A(end)];
3 Commenti
Stephen23
il 15 Gen 2015
Modificato: Stephen23
il 18 Gen 2015
This answer is very poor use of MATLAB.
The use of a for loop and concatenating scalar values onto the end of with every iteration is poor coding practice in MATLAB. If the arrays are large, then this will be slow as MATLAB keeps expanding the array and copying it to new memory. One solution is to preallocate the array.
For a much neater and simpler solution see my answer below.
Più risposte (1)
Stephen23
il 15 Gen 2015
Modificato: Stephen23
il 16 Gen 2015
This can be done simply using indexing, without any loops:
>> A = [1,3,5,7,9];
>> B = [2,4,6,8];
>> C(1:2:2*numel(A)) = A;
>> C(2:2:end) = B
C =
1 2 3 4 5 6 7 8 9
This solution also assumes that numel(A)==numel(B)+1.
Most importantly, for larger arrays this code will be much faster than the accepted solution, so it is the most universal solution.
0 Commenti
Vedere anche
Categorie
Scopri di più su Creating and Concatenating Matrices in Help Center e File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!