creating vector arrays from data set

Hi I have an hourly data set of electric load by day. E.g. for each day of Jan'00; I have 24 hours of electric load.I would like to create 31 separate vectors of length 24 (for each hour of the day) to hold the demand data for each day.

Here's my attempt:

numRows = length(dataset);
j=1
for i= 1:16:numRows
    [day.j]=ds2.Demand(i:i+16,1);
    j=j+1
end

I'm not sure how to create the right index for the d's. It should look like; d1 = (Hour1, Hour2...Hour 24), first day of data d2 = (Hour1, Hour2, ....Hour 24) of the second day of data

and so on and so forth...

Any suggestions on how to go? Thanks! C

[Jan]

It depends on how your "data set" is represented. An Excel file? A vector? A table object? Maybe a simple reshape is the solution already. Remember not to create 31 separate variables, but use a matrix instead. See https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval and https://www.mathworks.com/matlabcentral/answers/57445-faq-how-can-i-create-variables-a1-a2-a10-in-a-loop

[Chet Sharma]

Thanks Jan. The data set has been imported into matlab as a "ds". I'll look at the link you provided, hopefully it works!

[Chet Sharma]

Here's an image of the dataset. My final goal is to plot the data, so hour 24 hours of each day for each month.

[Chet Sharma]

[Chet Sharma]

Given that the ultimate aim is to chart by the column dOw, would it not be possible to write something like: plot(ds2.Demand,ds2.Hour,ds2.dos==2); Ideally, a chart for each separate day is what I'll need....I'm sure there's an easy trick...finding it hard to find as I'm rather new.

Answer 1

[Ahmos Sansom]

Hey,

Maybe convert column 2 to matlab datetime t = datetime(X,'ConvertFrom','Excel')

Then you cold select the data where weekday = 6 or Hour = 21 etc.

find(weekday(t) ==6)

This will give the index and then you can plot the respective values.

[Chet Sharma]

Thanks sir - I tried this, and it seems to work:

   delete(findall(0,'Type','figure'))

figure,hold on;
 count=1;
 x=linspace(1,24,24);
 for i=1:24:744
     plot(x,ds2.mwh(i:i+23,1));
%      day{count}=ds2.mwh(i:i+23,1);
        count=count+1
        legend('show');
 end
 xlim([1 24]);

   hold off;
  count

Now, I just need to extend it for the entire dataset, which has 12 months.

Answer 2

[Chet Sharma]

I think all answeres were useful here...so do I accept all answers (that were not provided by me, I mean)?

On another note, I found this awesome API called "plotly" (for those of you smiling, please be patient...I'm very new and still discovering), and it makes some solid interactive charts!

delete(findall(0,'Type','figure'))

figure,hold on;
 count=1;
 x=linspace(1,24,24);
 for i=1:24:744     

       plot(x,ds.load(i:i+23,1));     
  %      day{count}=ds2.mwh(i:i+23,1);                  
          count=count+1;
          legend('show');
   end
   xlim([1 24]);
  fig=fig2plotly(gcf);
   hold off;