How to fast process a calculation within a matrix without using a loop?
4 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
I have a huge matrix A, and what i need to do is to go through each of the matrix element and do this below simple calculation:
[m n] = size(A);
for i=1:m
for j=1:n
B(i,j) = 10^-A(i,j);
end
end
The thing is that it is slow. Is there a way I can avoid the loop and make it faster?
Thank you!
4 Kommentare
Rik
am 29 Mär. 2019
Bearbeitet: Rik
am 29 Mär. 2019
Whenever the size of an array increases, Matlab has to create a copy in memory. This takes a lot of time if you repeat that very often. Your original code would cause the output to be extended m+n-1 times.
Pre-allocation would solve this issue by creating an array in advance of the correct size. If array processing is not possible, it is generally worth it to pre-allocate the output array.
Akzeptierte Antwort
Weitere Antworten (0)
Siehe auch
Kategorien
Mehr zu Creating and Concatenating Matrices 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!