Combine data from 3 tables based on common datetime?

Dear reader,

I am currently working with three tables of measurement at different location. However, the time intervals of the measurements differ. For a proper analysis of the data, I only want to look at the dates and times at which all 3 measurements show a measurement. That is, the rows made bold in the example data below

The data from the different measurements is stored as follows (an example but not the entire table)

time_ERA5 Var2

____________________ _______

01-Jan-1990 00:00:00 0.39602

01-Jan-1990 01:00:00 0.39663

01-Jan-1990 02:00:00 0.3954

01-Jan-1990 03:00:00 0.39438

01-Jan-1990 04:00:00 0.3952

01-Jan-1990 05:00:00 0.3954

01-Jan-1990 06:00:00 0.3954

01-Jan-1990 07:00:00 0.39643

01-Jan-1990 08:00:00 0.40318

01-Jan-1990 09:00:00 0.41667

01-Jan-1990 10:00:00 0.40788

time_IFREMER Var2

____________________ _____

01-Jan-1990 00:00:00 0.448

01-Jan-1990 03:00:00 0.426

01-Jan-1990 06:00:00 0.392

01-Jan-1990 09:00:00 0.374

How can I obtain a table that only keeps the data for the datetime values that both tables have in common. The measured data (Var2 in both tables) is preferably stored in 2 seperate columns

Many thanks in advance!

Answer 1

[Kevin Holly]

Use innerjoin

Answer 2

[Sulaymon Eshkabilov]

Here innerjoin does not work. It is better to employ a logical indexing approach, e.g.:

% D1 is a first table array variable and D2 is a second one
V1 = D1.Var2(D1.time_ERA5==D2.time_ERA5);  % Gives only matching data points for Var2 in D1
V2 = D2.Var3(D1.time_ERA5==D2.time_ERA5);  % Gives only matching data points for Var2 in D2
% Makes up a new table variables
DD1 = D1(D1.Var1==D2.Var1,:);
DD2 = D2(D1.Var1==D2.Var1,:);
% if you want to put the selected data into DD1 or DD2, then
DD1.Var3 =[];
DD1.VarSel_1 = V1;
DD1.VarSel_2 = V2;
DD2.Var3 =[];
DD2.VarSel_1 = V1;
DD2.VarSel_2 = V2;

Answer 3

[Steven Lord]

Are you storing your data as table arrays or as timetable arrays? If the former, consider converting the table arrays to timetable arrays using table2timetable. Once you have your data stored as timetable arrays, you could synchronize those timetable arrays.