Stacking 2D matrix to 3D using time as a third variable

Hi I am a beginner in matlab and I am trying to stack 2D matrix into 3D matrix. I have variable sst as 1440*720 and time variable as 1*366. These are all daily data. How do I stack time to sst so that I have 366*1440*720 matrix. I have tried using cat and meshgrid but nothing seems to work. Thank you.

data.time = cat(3,data.time,data.sst)

or

[data.sst1]=meshgrid(data.sst,data.time); (this multiplies 1440*720 and gives me 366*1036800 matrix)

[Voss]

To end up with a 366*1440*720 array, you would need 366 individual 1440*720 matrices. In other words, you need a 1440*720 matrix for each time value. But it seems that you have one 1440*720 matrix and one scalar for each time value.

Put another way: a 366*1440*720 array has 366*1440*720 = 379,468,800 elements, but you have 366 + 1440*720 = 1,037,166 elements, not enough for a 366*1440*720 array.

If you had 366 individual 1440*720 matrices, then you could stack (and reshape/permute) them into a 366*1440*720 array (or a 1440*720*366 array, or whatever, as long as there's still 379,468,800 elements), but it doesn't seem like that's what you have.

[Ashal]

Thank you. I do have individual 366 1440*720 and I am using the following code to read data. So basically I have 366 different files that has sst(1440*720) and time values Here ii =366. I wish I could add data here but it is a huge folder.

gunzip("2020.zip.gz")

!ls 2020/oisst-*.nc>data.ptr

x = importdata('data.ptr'); %here x is cell array

for ii = 1:length(x);

data.time(ii) = ncread(x{ii},'time');

%ncdisp("2020/oisst-avhrr-v02r01.20200101.nc"); %ncdisp look inside nc file

data.sst = ncread(x{ii}, 'sst');

end

[Peter Perkins]

Just out of curiousity ...

366, OK, days in 2020 (although you may have a bug when you work on a non-leap year)

1440, OK, so maybe 24*60 minutes in a day?

What does 720 represent?

Or is 1440x720 a spatial lat/lon grid?

Answer 1

[Voss]

nx = numel(x);
data = struct( ...
    'time',zeros(1,nx), ...
    'sst',zeros(nx,1440,720);
for ii = 1:nx
    data.time(ii) = ncread(x{ii},'time');
    %ncdisp("2020/oisst-avhrr-v02r01.20200101.nc");  %ncdisp look inside nc file  
    data.sst(ii,:,:) = ncread(x{ii}, 'sst');    
end

That makes data.sst a 366*1440*720 array, as requested.

[Ashal]

It worked. Thank you so much.

[Voss]

You're welcome!