MATLAB: Need to import CSV file with date and time

csvimportdatetime

Dear all, I am a newbie to MATLAB frequently these days. I need to read time from the attached csv file and convert it into minutes. I had looked at many other questions similar to me but seems i am stuck!!
Scan, Time, Temp(C), Alarm 101 1, 01/09/2014 15:13:47:338, 25.408, 0 2, 01/09/2014 15:13:48:322, 25.373, 0 3, 01/09/2014 15:13:49:322, 25.372, 0 4, 01/09/2014 15:13:50:322, 25.373, 0 5, 01/09/2014 15:13:51:322, 25.368, 0
The time column need to be converted to mins and initial time instant need to be referenced. So i need to know the temperature change in mins. Thanks everybody!!

Best Answer

Use textscan to grab all of the data from file
 fid = fopen('Data_LDTT.csv');
 if fid>0
     % note how we skip the header lines and use the delimiter
     data = textscan(fid,'%d %s %f %d','Delimiter',',','HeaderLines',10);
     % close the file
     fclose(fid);
     % do stuff
 end
data will be a cell array, with its second column containing all of the date strings of the format
'01/09/2014 15:27:18:322'
You may then want to convert each string into a serial date number using datenum and then subtract from that serial date number, the equivalent for the reference time. For example,
 refTime    = datenum('01/09/2014 15.13.48','mm/dd/yyyy HH.MM.SS');
 curTime    = datenum('01/09/2014 15:27:18:322','mm/dd/yyyy HH:MM:SS:FFF');
 timeInMins = (curTime-refTime)*24*60
 timeInMins =
          13.5053667984903
The above assumes that the reference time is from the line
 Acquisition Date:,01/09/2014 15.13.48
Since the serial date number is the whole and fractional number of days from a fixed, preset date, then to convert to minutes, we must multiply by 24 (the number of hours in a day) and by 60 (the number of minutes in an hour). The 13.5 minute answer (above) seems reasonable given the two time strings.
Related Question