how to velocize it (vectorizing)

2 次查看（过去 30 天）
aldo
aldo 2023-8-20
编辑： Bruno Luong 2023-8-20
a=magic(10)
b=[4;5;9;2;3;4;2;7;4;9] %width(a) element
x=ones(size(a));
for i=1:numel(b)
x(1:max(b(i)-1,1),i)=0
end

请先登录，再回答此问题。

回答（1 个）

Bruno Luong
Bruno Luong 2023-8-20
编辑：Bruno Luong 2023-8-20
Ran in:
I don't know why a is matter beside that the first dimension is 10
a=magic(10);
b=[4;5;9;2;3;4;2;7;4;9]; %width(a) element
h = size(a,1);
x = double(ndgrid(1:h,b)>=b(:)')
x = 10×10
0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 1 1 0 1 0 0 0 1 0 0 1 1 1 1 0 1 0 1 1 0 1 1 1 1 0 1 0 1 1 0 1 1 1 1 0 1 0 1 1 0 1 1 1 1 1 1 0 1 1 0 1 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
;
  9 个评论
显示 7更早的评论
aldo
aldo 2023-8-20
编辑：aldo 2023-8-20
"Yes for-loop is faster on onlive server (on my compter I get the opposite)." i don't use online server but my pc "Processore AMD Ryzen 9 5950X 16-Core Processor, 3401 Mhz, 16 core, 32 processori logici"
I think is better to use loop in my pc because it work with parallel processor
I've noticed dramatic improvements when it comes to vectorizing code where there is a loop inside another
thanks for taking the time
Bruno Luong
Bruno Luong 2023-8-20
编辑：Bruno Luong 2023-8-20
"I've noticed dramatic improvements when it comes to vectorizing code where there is a loop inside another"
Not really. The speed depens what you do in the body of the loop(s), not loop are nested or not.
I know what I'm talking on speeding MATLAB code.

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Startup and Shutdown 的更多信息

标签

Community Treasure Hunt

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

Start Hunting!

Translated by