Reorder vector without for loop

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Science Machine
Science Machine on 3 Oct 2022
Edited: Chunru on 3 Oct 2022
I would like to do the following without using the for loop:
for delta=1:540 % get circle points from the line.
vectorB((delta-1)*(1080)+1:(delta)*(1080),:)=vectorA(delta:540:583200,:); % both vecs of size 583200x1000
end % delta
This loop grabs every 540th point in a vector, stores, then increments the amount by 1 and repeats,...,etc.
Is it possible to use a built in function to do the same? Also, I plan to export to C, so whatever function must be supported.
Currently, matlab is more performant than the C coder result.

Answers (1)

Chunru
Chunru on 3 Oct 2022
Edited: Chunru on 3 Oct 2022
A = randn(583200, 10);
B =reshape(A, 540, [], 10);
B = permute(B, [2 1 3]);
B = reshape(B, 583200, 10);
whos
Name Size Bytes Class Attributes A 583200x10 46656000 double B 583200x10 46656000 double cmdout 1x33 66 char
% To verify the results
A(1:540:end, 1) % every 540th points
ans = 1080×1
0.3265 -0.1556 1.3238 -0.5684 -0.7725 -1.6892 1.3998 -1.0533 1.1349 2.0951
B(1:10, 1) % 1st 10 points
ans = 10×1
0.3265 -0.1556 1.3238 -0.5684 -0.7725 -1.6892 1.3998 -1.0533 1.1349 2.0951
  4 Comments
Science Machine
Science Machine on 3 Oct 2022
you made A = randn(583200, 1); but its A = randn(583200, 1000); In that case A and B don't have the same dimension
Chunru
Chunru on 3 Oct 2022
Edited: Chunru on 3 Oct 2022
OK. Now A & B are of the size you specified. (use a smaller value for 2nd dimension)

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