Ismember as a condition?

Hello guys.

I am trying to achieve something easy I think, but I don't know the correct way.

I have two tables, let's say WRF and Obs, that contain hourly values of several variables. What I want to do is calculate things and produce graphs, for the dates that both tables have data.

Eg, WRF contains data from 1/7/2019 to 30/9/2019 and Obs from 31/3/2019 to 30/9/2019.

I tried

ismatch = ismember(Obs.Hourly_DATE, WRF.Date);

which returns 0s kai 1s. How do I take one step further and use the 1s to calculate the things I want?

Thank you in advance!

[Mohammad Sami]

Are the timestamps in data exact match and equally spaced ?

If not I would suggest that you use timetable and combine the two timetables with the synchronize function.

newtable = innerjoin(Obs,WRF,'LeftKeys','Hourly_DATE','RightKeys','Date');

[Daphne PARLIARI]

Yes, the format I used is the same.

[Mohammad Sami]

Ok the innerjoin should then correctly merge the two tables together on the common datetime values. Do verify the newtable created before using it further.

[Daphne PARLIARI]

Something goes wrong... Attached please find the Obs table, the WRF table and newtable.

Newtable is far too long. I think the problem is that I have to consider columns Time, also (for both tables, WRF and Obs).

Answer 1

[Mohammad Sami]

Yes needed to combine with the time column.

load Obs.mat
load WRF.mat
WRF_Data.Date = WRF_Data.Date + duration(hour(WRF_Data.Time),minute(WRF_Data.Time),0)
Obs_Data.Hourly_DATE + duration(string(Obs_Data.Time),'InputFormat','hh:mm');
newtable = innerjoin(Obs_Data,WRF_Data,'LeftKeys','Hourly_DATE','RightKeys','Date');

[Daphne PARLIARI]

Works fine with a mistake though:

In newtable, column Time_WRF_Data is in datetime format and it appears 00:00 in all rows....

[Daphne PARLIARI]

The mistake I mentioned above is easily corrected this way:

WRF_Data.Date = WRF_Data.Date + duration(hour(WRF_Data.Time),minute(WRF_Data.Time),0);
Obs_Data.Hourly_DATE = Obs_Data.Hourly_DATE + duration(string(Obs_Data.Time),'InputFormat','hh:mm');
All_Data = innerjoin(Obs_Data,WRF_Data,'LeftKeys','Hourly_DATE','RightKeys','Date');