How to select specific data from one matrix and place it in another

Hello,

I have the following problem. I have a large matrix A (1X960). At positions 336 I have the prices for 14 consecutive Mondays. That is, every Monday has 24 prices. Then, in the next 312 positions I have data for 13 consecutive Fridays (every Friday has 24 prices) and in the last 312 positions I have data for 13 consecutive Saturdays (every Saturday has 24 prices).

What I'm trying to do is this: In a new matrix B I want to put the data in order. That is, to enter first the 24 values ​​of Monday, then the 24 values ​​of Friday and then the 24 values ​​of Saturday. This should continue for all the data in matrix A. Your help is important !!!

[Rik]

What have you tried so far?

Answer 1

[Ameer Hamza]

Try this

data = 1:960;

A = reshape(data, 24, []).';
B = zeros(size(A));
B(1:3:end, :) = A(1:14, :);
B(2:3:end, :) = A(15:27, :);
B(3:3:end, :) = A(28:40, :);

B = reshape(B.', 1, [])

[stelios loizidis]

Okay, it works!! I have a question. I have a datetime that has the corresponding dates and I would like to do it in the same way as you suggest. How can it be done?

[Ameer Hamza]

Replace

B = zeros(size(A));

with

B = NaT(size(A));

For example, try the following code

data = linspace(datetime('now')-1, datetime('now'), 960);
A = reshape(data, 24, []).';
B = NaT(size(A));
B(1:3:end, :) = A(1:14, :);
B(2:3:end, :) = A(15:27, :);
B(3:3:end, :) = A(28:40, :);
B = reshape(B.', 1, [])

[stelios loizidis]

It. works!!!!!!!Thank you very much for the valuable help!

[Ameer Hamza]

I am glad to be of help! :)

Answer 2

[Cris LaPierre]

See Ch 5 of MATLAB Onramp.

Answer 3

[dpb]

The following can be optimized, but if I understand you want the data reordered by hour for each day, then the basic idea for any number of days and observations per day assuming every daily observation is complete set of numPerDay.

nDays=[14,13,13];
numPerDay=24;
dIx=nDays*numPerDay;
ix1=[1 cumsum(dIx(1:numel(nDays)-1))+1];
for i=1:24
  B(i,:)=A(ix1);
  ix1=ix1+1;
end