How to repeat a 4d vector for n times

Hi,

I have a 4d vector, W of size (1 x 1 x 8 x 100). I want to reshape the vector of size (1 x 1 x 8 x 1000) where the value of W will be copied after every 100 dimension.

Input:

W =val(:,:,1,1) =  -0.0018
val(:,:,2,1) =    0.0045
... ... ... ... ... ... ... ... ...
val(:,:,8,100) = 0.0034

Output:

Then after my desired computation W turns to be like this

val(:,:,1,1) =  -0.0018
val(:,:,2,1) =    0.0045
... ... ... ... ... ... ... ... ...
val(:,:,8,100) = 0.0034
val(:,:,1,101) = -0.0018
val(:,:,2,101) =    0.0045
... ... ... ... ... ... ... ... ...
val(:,:,8,200) = 0.0034
val(:,:,1,201) = -0.0018
val(:,:,2,201) =    0.0045
... ... ... ... ... ... ... ... ...
val(:,:,8,300) = 0.0034
... ... ... ... .. ... ... ... ... ...

I am thinking to do this using procedural style but I think MATLAB haas much faster way to dot this computation which I do not know. Can you please advice me in this regard?

thanks,

Answer 1

[Stephen23]

Z = repmat(W,1,1,1,10)

[Saugata Bose]

@Stephen: thanks. its so simple implementation wherever I am writing a few lines of procedural code for this. Does this simple code mean that repmat copy W 10 times? in that case, what does other 1 mean here?

[Stephen23]

"Does this simple code mean that repmat copy W 10 times? in that case, what does other 1 mean here?"

According to the repmat documentation: "B = repmat(A,r1,...,rN) specifies a list of scalars, r1,..,rN, that describes how copies of A are arranged in each dimension. When A has N dimensions, the size of B is size(A).*[r1...rN]. For example, repmat([1 2; 3 4],2,3) returns a 4-by-6 matrix."