MATLAB: How to repeat monthly data over several years

MATLABmatrix manipulation

Hello,

I have a potentially simple question.

I have a spatial matrix A=144x192x1x12. The fourth dimension is time in months.

I would like to make a matrix where I have 30 years of repeated data B=144x192x1x360.

I have tried something along the lines of-

for i=1:12;
B(:,:,:,i:12:360)=A(:,:,:,i);
end

But of course this did not work due to differnce sizes of each side.

How would I achieve this simple copying of each year for 30 years?

Thank you,

Holly

Best Answer

Matlab has a function for concatenating values in different dimensions, you could solve your problem like this:

A = randn(144,192,1,12);
B = [];
for i=1:30
B = cat(4,B,A);
end
size(B)
ans =
   144   192     1   360

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Copying your X array, I find

>> Nyr=length(X)
Nyr =
  51

instead of 52...minor point perhaps you missed a datapoint in the posting. Anyway, that aside--

yr=1956:1956+Nyr-1;   % generate a year vector to match...
figure
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ylim=[yr(1) yr(end)]  % set x-limits to data bounds
set(gca,'fontsize',9) % maybe you like the looks of this "more better"??

For two-digit years,

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Doing the labels this way makes sure you've got the same number as the number of ticks -- labels and ticks have to be 1:1 or won't use 'em all (if too many) or will repeat (not enough).

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Best Answer

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