I have a text file having 7 columns. First column is UTC time in hours. This file is having data for almost 1 month. i need to separate data day wise and save it to different day . whenever first column value is > than 0.00, a new day is starting

please suggest something. i am new to matlab

Answer 1

[Akbar]

First I have imported your data to matlab using its 'import data' tool. And created a table called 'anci'. Whose size is 5003x7. Where VarName1 is the first column. This code creates a cell Array for each new day. I got a cell Array called 'days' which is of size 37. So, your dataset contains 37 days. When you click on any cell you can see data collected for that particular day. I noticed that most of the days contain about 133 records. Please accept my answer.

%if the difference between previous row and next is 
%more than 22, then record the index because thats where a
%new day starts. 
k=1;
for i = 2:height(anci)
    if abs(anci.VarName1(i) - anci.VarName1(i-1))>22
    ind(k) = i;
    k=k+1;
    end
end
days = cell(length(ind),1); %preallocates dimensions  
days{1,:} = anci(1:ind(1)-1,:); % first day
for i = 2:length(ind) % starting from second day

      %creates cell array that contains tables; each cell beginning with 
      %index ind(i) of table anci, ending on index ind(i+1)-1
      if i ~= length(ind) %if not last pass
          days{i,:} = anci(ind(i):ind(i+1)-1,:);
      else
          days{i,:} = anci(ind(i):end,:);
      end
  end

[Neha gupta]

Why first day data is taken separately?

[Akbar]

Because the ind vector doesn't contain the very first row index 1, so i included it manually. And wrote like this: 1:ind(1)-1

 days{1,:} = anci(1:ind(1)-1,:); % first day

[Neha gupta]

ok thank you.