I created an 3D sinusoidal surface. And want to add a normally distributed random noise of zero mean and 0.03mm standard deviation. But it said error on the line with*. Subscripted assignment dimension mismatch. could someone help me check it please

Question

Jianxiang 2013-8-19

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/85120-i-created-an-3d-sinusoidal-surface-and-want-to-add-a-normally-distributed-random-noise-of-zero-mean

回答： muna majeed 2015-8-4

%3D sinusoidal surface dx=0.001; %spacing in x in mm dy=0.001; %number of points along x and y nx=128; ny=128; %n=8000; %generate array of x & y x=(0:1:nx-1)*dx; y=(0:1:ny-1)*dy; for j=1:ny for i=1:nx z(j,i)=2*sin(2*pi*x(i)/0.064)+normrnd(0,0.03*ones(nx,1)); end end z=z-mean(mean(z));%shift to 0 mean mesh(x,y,z)

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Youssef Khmou 2013-8-19

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/85120-i-created-an-3d-sinusoidal-surface-and-want-to-add-a-normally-distributed-random-noise-of-zero-mean#answer_94625

编辑：Youssef Khmou 2013-8-19

在 MATLAB Online 中打开

Jianxiang,

As you use x,y loops , at each iteration the CPU computes only one scalar while you used the function normrnd of size 128*1, you can adjust your method :

%3D sinusoidal surface
dx=0.001; %spacing in x in mm 
dy=0.001; %number of
%points along x and y 
nx=128; ny=128; %
n=8000; %generate array of x & y 
x=(0:1:nx-1)*dx; 
y=(0:1:ny-1)*dy; 
for j=1:ny 
  for i=1:nx 
      z(j,i)=2*sin(2*pi*x(i)/0.064)+normrnd(0,0.03);
  end
end
z=z-mean(mean(z));%shift to 0 mean mesh(x,y,z)