清空筛选条件
清空筛选条件

Sine wave

1 次查看（过去 30 天）
simira atraqi
simira atraqi 2012-4-16
评论： Walter Roberson 2023-2-16
Hello Everyone,
With these codes, the matrix A have 4000 points and this take a long time, how can I let this program work quickly with less Matrix and the same wavelength 100 um?
Thanks
xRes = 1; % Sets the resolution (step length), in µm, along the x-axis.
yRes = 1; % Sets the resolution (step length), in µm, along the y-axis.
zRes = 1; % Sets the resolution (step length), in µm, along the z-axis.
xLength = 4000; % Sets the length of the surface in X.
yLength = 3000; % Sets the length of the surface in Y.
wavelength = 100;
f = @(x) 3*sin(x*2*pi/wavelength) + 1003; % The function for the sine wave with the
% amplitude 3 µm and wave length of about 100 µm. Mean level is
% 1003 µm.
% Prints the sine wave into a matrix:
A = zeros(yLength/yRes+1,xLength/xRes+1);
for k = 1:length(A(:,1))
for l = 1:length(A(1,:))
A(k,l) = f(l-1);
end
end

请先登录，再回答此问题。

回答（1 个）

Walter Roberson
Walter Roberson 2012-4-16
All of your rows are the same, so consider using repmat()
  2 个评论
simira atraqi
simira atraqi 2012-4-16
I am sorry but I didn't get it. What you mean?
Walter Roberson
Walter Roberson 2023-2-16
for k = 1:length(A(:,1))
for l = 1:length(A(1,:))
A(k,l) = f(l-1);
end
end
You are not changing f within the loops, so A(1,5) = f(4) and A(2,5) = f(4) and A(3,5) = f(4) and so on -- each A(k,l) is exactly the same as A(k-1,l) . Therefore you only need to build A(1,:) and then you copy the row as many times as needed.
for l = 1 : size(A,2)
A(1,l) = f(l-1);
end
A = repmat(A(1,:), size(A,1), 1); %replicate the row

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Tables 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