Get Data from a 16414x6 array to 365 arrays with size(48x3)

Hello,

I Have an array that consist meteorological Data for 365 days.

For every day (24 Hours) i have 48 entries in that table because it is seperated for every 30 minutes.

That gives me a table with 16414 rows and 6 coloums.

What i need is to seperate the days in different tables with only 3 of the coloums of the original one.

For example i want to have 365 tables with size (48,3)

Answer 1

[Andreas Tsiartas]

I came up with a different solution. I am attaching it here if it helps anyone.

I basically created an index for eax individual array i was trying to create. I scanned over the whole table and then assigned the values to different arrays to work with the values

IndxFeb=1;
IndxMar=1;





LenghtDataset = height(Dataset_Table); %Get the number of rows in the Dataset_Table




%Checks the Timestap to assign values to the correct arrays
for i=1:size(Dataset_Table)   
    
%----------------------------------------------------------------------
%Check if it's January
if (Dataset_Table{i,1} <= datetime(2019,01,31))
    JanuaryTime(i)= Dataset_Table{i,1};
    JanuaryGHI(i)= Dataset_Table{i,4};
    JanuaryTamp(i)= Dataset_Table {i,6};
end
%----------------------------------------------------------------------
                        %End of January Test
%----------------------------------------------------------------------
    

%----------------------------------------------------------------------
%Check if it's February
if (Dataset_Table{i,1} >= datetime(2019,02,01) && Dataset_Table{i,1} <= datetime(2019,02,29))
    FebruaryTime(IndxFeb)= Dataset_Table{i,1};
    FebruaryGHI(IndxFeb)= Dataset_Table{i,4};
    FebruaryTamp(IndxFeb)= Dataset_Table {i,6};
    IndxFeb = IndxFeb + 1;
end
%----------------------------------------------------------------------
                        %End of February Test
%----------------------------------------------------------------------



%----------------------------------------------------------------------
%Check if it's March
if (Dataset_Table{i,1} >= datetime(2019,03,01) && Dataset_Table{i,1} <= datetime(2019,03,31))
    MarchTime(IndxMar)= Dataset_Table{i,1};
    MarchGHI(IndxMar)= Dataset_Table{i,4};
    MarchTamp(IndxMar)= Dataset_Table {i,6};
    IndxMar = IndxMar + 1;
end
%----------------------------------------------------------------------
                        %End of March Test
%----------------------------------------------------------------------

.......

[Rik]

You are making your life needlessly complicated. If you discover you want a minor change, you will now have to change your code in 12 places, instead of 1. It is of course up to you, but I would seriously suggest using something else. You can even use the month function to index that array:

x={'jan','feb','mar'};
x{month(datetime)}%datetime without input returns the current date and time

ans = 'feb'

[Andreas Tsiartas]

I didn't know about that function. That's great news!

This is the first time i am using MATLAB for some Data Analysis.

I will try it and update the post!

Thank you Rik!

Answer 2

[Rik]

I would suggest using a 3D array instead. If you dynamically generate variable names you are shooting yourself in the foot. You can use the reshape function to reshape your data to a 3D array.

[Andreas Tsiartas]

First of all Thanks for your time. I tried it but i found a different solution that did the job!