How to Increment matrix

Hello I am new to Matlab.

I have been trying to increment a 1 by 3 matrice (basically time in Hh:mm:Ss.sss) by 30 seconds, n number of times. What's the best way to do this?

Thank you!

[KALYAN ACHARJYA]

I am not getting your question. Though its answer seems simple, please clarify.

[the cyclist]

Please give an example of your matrix. There are a few ways to store a date/time value in MATLAB.

[Andrew Dicom]

Sorry :/ It's basically something like this e.g [15 25 01] I want to to increment it by 30 seconds for 180 times.

So the output will look like this:

15 25 01

15 25 31

15 26 01

Etc...

I know it probably sounds simple but it's one of my first time using this program...

I'm using R2012a so datetime can't really function here and I've tried installing it but it still seems not to work... Is there another way?

Thank you and sorry if it sounds like a juvenile question.

[Image Analyst]

Don't do it like that. Use official time variables instead of trying to keep track of all the parts of time yourself. It will be so much easier. See answer below for one way.

Answer 1

[KL]

start_t = datenum('15:25:01','HH:MM:SS')
step_t = datenum('15:25:31','HH:MM:SS')-datenum('15:25:01','HH:MM:SS');
end_t = datenum('16:55:01','HH:MM:SS')
ts = start_t:step_t:end_t;
ts_dvec = datevec(ts);

[Andrew Dicom]

Hello. Thank you so much for the reply. Will this work if I wanted to replicate it to produce 200 number of 30 second increments as well?

[KL]

Yes, you should just change the end time ( end_t).

[Andrew Dicom]

Hello KL, Thank you so much for the reply! The script works great and helped a lot. In the script you wrote, I'll have to manually key in the HH:MM:SS each time I run. But what if I wanted it to read it from a few hundred .mat files like the following:

load('ACT2007-sh.mat')

M = D.other.info.hour;

%M = 15:25:01 (example only, value may vary depending on .mat file)in HH:MM:SS;

I want to create 180 epochs of 30seconds for M I will be repeating this process with multiple .mat files so it would not be ideal to calculate the final epoch for n=180 for each one.

[KL]

your_folder = 'YOUR_FOLDER_PATH'; %folder where mat files are there
folderInfo = dir([your_folder '/*.mat']); 
fnames = {folderInfo.name};
n = 180; %your count
for iFile=1:numel(fnames)
    S = load(fullfile(your_folder,fnames{iFile}));
    starttime = S.yourvarname; %must be a text in 'HH:MM:SS' format
    start_t = datenum(starttime,'HH:MM:SS');
    step_t = 3.47222e-4;
    end_t = start_t+(step_t*n);
    ts = start_t:step_t:end_t1;
    %%do whatever you want
end

[Andrew Dicom]

thanks!