Finding values on only time (excluding date)

[KL]

How have your stored your data? which version are you using?

[sikander shahzad]

Each column is stored in separated variable.

[sikander shahzad]

variables are value1 (6 x 1) double, value2 (6 x 1) and value3 (6 x 1). whereas date/time is (6 x 1) cell array.

Answer 1

[Cam Salzberger]

Hello Sikander,

If you can import your data and get it into a datetime format - readtable is good for this - then this is pretty easy. Just use timeofday to drop the date portion of the datetime.

-Cam

Answer 2

[Andrei Bobrov]

T = readtable('data1.xlsx');
T.Date_Time = datetime(join(string(T{:,1:2})),'I','dd-MM-uuuu HH:mm');
T = T(:,[1,3:end]);
out = T(hour(T{:,1}) == 8,:);

[sikander shahzad]

I have data with many row. kindly show me the way to use find function and with the help of index i can fetch required result.

[Cam Salzberger]

You generally shouldn't need to use the "find" function. It is often more efficient to just use logical indexing directly. That is what is being done with Andrei's example. The expression:

logicalArray = hour(T{:, 1}) == 8;

will produce a logical array of the same number of rows as T, with "true" whenever the hour value in the first column of T is 8. When you do:

T(logicalArray, :)

it will return only those rows that were "true" in the logical array.

-Cam