extract data from one day from a timetable

Hello everybody

I've a timetable with multiple variabiles and the time column containg both day and hour information. If I choose a day I would like to be able to extract from timetable all data collected during that day (that are many).

Now if I try to do that I only manage to extract the first value for that day, but remaing ones (after midnight) are not collected.

t0 = datetime(2006,01,01);

TT2.LivelloIdrometricoCorr(TT2.InizioValiditUTC(t0));

Answer 1

[Star Strider]

Try something like this —

LD = load('ask_matlab.mat');

TT1 = LD.ans;

RT = TT1.Properties.RowTimes;

VN = TT1.Properties.VariableNames;

DayMthLv = day(RT) == 1 & month(RT) == 1; % Logical Vector

Mon1Day1 = TT1(DayMthLv,:) % Data For January 1, 2006

Running that code offline (since .mat files are not yet supported here) produces the appropriate result, a (48x2) timetable of the selected dates.

.

[Fabio]

Thank you,

I've actually tried to use your code adding:

DayMthLv = day(RT) == giorno & month(RT) == mese & year(RT) == anno; % Logical Vector

and performing an implementation with 3 for cycles, in order to execute this operation for each day from my time series.

I'm gonna make an attempt to verify if it works,

thank you for help and support.

Have a nice week end

[Star Strider]

As always, my pleasure!

You, too!

.

Answer 2

[Steven Lord]

Use a timerange. First generate some sample data with datetime values representing random hours in July 2022.

rng default % for reproducibility
dt = datetime(2022, 7, randi(31, 10, 1), randi([0 23], 10, 1), 0, 0);
x = (1:10).';
tt = timetable(dt, x)

tt = 10×1 timetable
             dt             x 
    ____________________    __

    26-Jul-2022 03:00:00     1
    29-Jul-2022 23:00:00     2
    04-Jul-2022 22:00:00     3
    29-Jul-2022 11:00:00     4
    20-Jul-2022 19:00:00     5
    04-Jul-2022 03:00:00     6
    09-Jul-2022 10:00:00     7
    17-Jul-2022 21:00:00     8
    30-Jul-2022 19:00:00     9
    30-Jul-2022 23:00:00    10

Let's retrieve all the rows of tt from July 4th. We make a timerange that starts at midnight on the 4th and ends just before midnight on the 5th.

fourth = datetime(2022, 7, 4);
tr = timerange(fourth, fourth+days(1))

tr = 
	timetable timerange subscript:

		Select timetable rows with times in the half-open interval:
		[04-Jul-2022 00:00:00, 05-Jul-2022 00:00:00)

	See Select Timetable Data by Row Time and Variable Type.

Finally use tr to index into tt.

dataFromFourth = tt(tr, :)

dataFromFourth = 2×1 timetable
             dt             x
    ____________________    _

    04-Jul-2022 22:00:00    3
    04-Jul-2022 03:00:00    6