Adding time and date column to text file

I have a txt file with thousand of rows and 8 columns, example for 1 row is below

1111 2222 3333 4444 5555 6666 7777 8888

I want to add date and time as format below

3/24/2021 3:33:30 PM 1111 2222 3333 4444 5555 6666 7777 8888

Logging started 3/24/2021 at 3:33:30 and it logged after every 2 second. so the time should increase by 2 second for each row until the last n row.

3/24/2021 3:33:30 PM 1111 2222 3333 4444 5555 6666 7777 8888

3/24/2021 3:33:32 PM 1312 2003 3133 4423 5232 6123 7712 8812

.

.

.

3/25/2021 1:12:15 AM 3132 3123 5645 3242 3546 1321 1313 1215 ( this an example of the last ending row)

Please help me in this case. thank you very much.

Answer 1

[Adam Danz]

1. Read in the file
2. Create vector of datetime values (see below)
3. Create a time table with the datetime vector and data from the file
4. Use writetimetable to write the data back into a text file.

To create the datetime vector

n is the number of rows of data which you can get after reading in the file.

n = 1000; 
startingDate = datetime(2021,3,24,15,33,30,'Format','MM/dd/yyyy hh:mm:ss a');
t = startingDate + seconds(0:2:n*2-1)'

t = 1000×1 datetime array
   03/24/2021 03:33:30 PM
   03/24/2021 03:33:32 PM
   03/24/2021 03:33:34 PM
   03/24/2021 03:33:36 PM
   03/24/2021 03:33:38 PM
   03/24/2021 03:33:40 PM
   03/24/2021 03:33:42 PM
   03/24/2021 03:33:44 PM
   03/24/2021 03:33:46 PM
   03/24/2021 03:33:48 PM
   03/24/2021 03:33:50 PM
   03/24/2021 03:33:52 PM
   03/24/2021 03:33:54 PM
   03/24/2021 03:33:56 PM
   03/24/2021 03:33:58 PM
   03/24/2021 03:34:00 PM
   03/24/2021 03:34:02 PM
   03/24/2021 03:34:04 PM
   03/24/2021 03:34:06 PM
   03/24/2021 03:34:08 PM
   03/24/2021 03:34:10 PM
   03/24/2021 03:34:12 PM
   03/24/2021 03:34:14 PM
   03/24/2021 03:34:16 PM
   03/24/2021 03:34:18 PM
   03/24/2021 03:34:20 PM
   03/24/2021 03:34:22 PM
   03/24/2021 03:34:24 PM
   03/24/2021 03:34:26 PM
   03/24/2021 03:34:28 PM

[Dung Tran]

that works really good. Thank you Mr. Adam