splitapply with own created function

I have 'nr' tables containing the following: date/time/Qdot/temperature

i would like to apply a function to this tables more specific i would like to apply a function on data grouped by day (date)

herefor i've tried to use the function splitapply where the function is of my own creating

for j=2:24
    s = (j-1); %sizetimestep - 1stap
    for i=1:nr
       [G,days] = findgroups(DayT{i}.date);
        
       max_Qdot = splitapply(@maxperinterval,DayT{i}.Qdot,s,G);        
       Mean_T = splitapply(@mean,DayT{i}.Temperature,G);
       Max_tabel{j,i}=table(days,max_Qdot,Mean_T,'VarbiableNames',rownames);
    end
end

But when i tried to run this i get an error saying the following:

"The data variables must have the same number of rows as the vector of group numbers. The group number vector

has 5736 row(s), and data variable 2 has 1 row(s)."

My own function needs the input of variable s.

Is this even possible to use this function with splitapply?

Answer 1

[Rik]

You can probably get around this by wrapping your function in an anonymous function:

fun=@(input1)maxperinterval(input1,s);

max_Qdot = splitapply(fun,DayT{i}.Qdot,G); 

Now the function splitapply is looking at only requires 1 input variable while your function will receive both. Note that you will need to generate fun every time you update s.

[Senne Van Minnebruggen]

Thanks! This solved my problem.

Answer 2

[Ameer Hamza]

As the error indicate. The error is related to the orientation of matrices. Change it like this

max_Qdot = splitapply(@maxperinterval,DayT{i}.Qdot,s.',G);  % use transpose of s so that it become column matrix