I have an excel file ... which consists of 1st column is dates and time and other n rows and n columns data.... in this file, I have daily 1-hour data, I want day night data separate for the reference I have attached output file. Please find input an

Please see the input and output file attachment for reference.

[John Chilleri]

How do you define day/night (by the hour or by the minute and hour)?

[Sunil Oulkar]

from morning 6 am to 5:59 pm day and 6 pm to 5:59 am night

[Sunil Oulkar]

I want day data and night data in two separate file

Answer 1

[Peter Perkins]

I recommend using readtable, using the %D format to create datetimes. Then it's easy to select rows of the table by day and night using timeofday. Then use writetable to write out the separate data.

[John Chilleri]

I'm going to have to check this out for myself! Always enlightening to hear of built in solutions!

Answer 2

[John Chilleri]

Hello,

Here is code that does what you want. You'll need to have two blank files in your directory named "outputfileDAY.csv" and "outputfileNIGHT.csv" - it will write day and night to these files respectively. Furthermore, you need to have "inputfile.csv" in your directory from which the code will pull the data, please have it in csv format. Note that your input/output files have a different number of entries so it was weird to compare, but I checked the results and the code worked:

% Code to separate by time
%
% Acquiring and splitting data
fid = fopen('inputfile.csv','rt');
dayandnight = textscan(fid,'%s %f %f %f %f', 'Delimiter', ',',... 
  'CollectOutput', 1);
%
% Acquiring times from date
fileid1 = fopen('outputfileDAY.csv','w');
fileid2 = fopen('outputfileNIGHT.csv','w');
for i = 1:size(dayandnight{1},1)
  Time = dayandnight{1}{i}(end);
  j = 0;
  while (Time(1) ~= ' ')
      Time = dayandnight{1}{i}(end-j:end);
      j = j+1;
  end
  Time = Time(2:end);
  if (Time(2) == ':')
      Time = Time(1);
  else
      Time = Time(1:2);
  end
  if ((str2num(Time) >= 6)&&(str2num(Time) < 18))
      fprintf(fileid1,'%s,%f,%f,%f,%f\n',dayandnight{1}{i},dayandnight{2}(i,1),...
          dayandnight{2}(i,2),dayandnight{2}(i,3),dayandnight{2}(i,4));
  else
      fprintf(fileid2,'%s,%f,%f,%f,%f\n',dayandnight{1}{i},dayandnight{2}(i,1),...
          dayandnight{2}(i,2),dayandnight{2}(i,3),dayandnight{2}(i,4));
  end
end
fclose(fileid1);
fclose(fileid2);

Please comment if you have any questions!

Hope this helps!

[Jan]

strtim is more efficient and clear than the while (Time(1) ~= ' ') loop.

This is a straight and clear approach, +1.

[John Chilleri]

Never heard of strtrim before, I'll be sure to incorporate that into my programming!

Thanks for the knowledge!