Sub-scripting a table

Hi everyone,

I have an 8928x41 table with datetime values in the first column. I am trying to group the values in this table according to time.

I have done this with a similar table to retrieve data for particular monthsa and yeasr as below:

T1=T(2010==year(T.Date),:); % Retrieves the data for the year 2010
T2=T(7==month(T.Date),;); % retrieves the data for July

I assume that if I do the same thing for the hour, it will yield the results but below is a sample of the results I got from the data set

hour20=MarchData(20==hour(MarchData.Date),:);

How can I get data for hour 20 (20:00) alone?

Secondly Can someone help me write an iteration to do this for the 24 hours in a day?

Thank you.

[Peter Perkins]

It's not really clear what you are asking. If you want the one row for 8pm on that day, you aren't grouping anything. And it's not clear what you want to do with the groups of data.

In any case, it usually true that you don't need to explicitly separate the data into groups. Things like varfun, groupsummary, and splitapply are happy to work across all groups for you.

Consider puttig your data in a timetable, and using retime with one of the aggregation syntaxes to reduce your data to hourly values, if that's what you are trying to do.

Answer 1

[per isakson]

Try and replace

hour20=MarchData(20==hour(MarchData.Date),:);

by

clock2000 = MarchData((hour(MarchData.Date)==20 & minute(MarchData.Date)==0),:);

[Lui]

Thank you. This worked