For loop
1 回表示 (過去 30 日間)
古いコメントを表示
hi 2 all, Can anyone say how to reduce execution time of 'for loop' in matlab How to replace for loop?
採用された回答
Andrei Bobrov
2011 年 8 月 16 日
u1 = 255*sign(ima);
but you get the array size is 1600 x 1600, with values of -255, 0 and 255
ADD on comments
if i1 and j1 integers from 1 to 1600, we obtain an array of 1600 by 1600, consisting of ones, in it case use
i1 = linspace(0,1,6);
j1 = i1;
T=cos(2*pi*repmat(i1',1,numel(j1))).*cos(2*pi*repmat(j1,numel(i1),1)); % 1 variant
T = bsxfun(@times,cos(2*pi*i1'),cos(2*pi*j1)); % 2 variant
T = cos(2*pi*i1')*cos(2*pi*j1);% 3 variant
その他の回答 (1 件)
Walter Roberson
2011 年 8 月 16 日
The one sure way to reduce the execution time of a for loop is to eliminate that section of code.
Anything else depends on exactly what your for loop contains. There are some for loops that are now faster than vectorizing or using one of the library routines -- faster even than using a mex routine.
参考
カテゴリ
Help Center および File Exchange で Loops and Conditional Statements についてさらに検索
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!