How would I write this code?

I have data like this:

Fourth column is time in UTC/Zulu and the fifth column is stage observations.

1	1	2015	0	3.48
1	1	2015	6	3.48
1	1	2015	12	3.46
1	1	2015	18	3.43
1	2	2015	0	3.39
1	2	2015	6	3.33
1	2	2015	12	3.27
1	2	2015	18	3.21

I am trying to use the find function to index the data correctly.

This is what I have so far but I keep getting errors.

ind = find((obs(:,1)== month) & (obs(:,2) == day) & (obs(:,3) == year) & (obs(:,4) == time));

These are the errors that continue to pop up.

>> COMO2_2015
Error using month (line 44)
Please enter D.

Error in COMO2_2015 (line 5)
ind = find((obs(:,1)== month) & (obs(:,2) == day) & (obs(:,3) == year) &
(obs(:,4) == time));

Answer 1

[Cris LaPierre]

What is month?

You are using it as a variable. However, if you have not defined it as a variable, then MATLAB is trying to call the month function. However, doing so without inputs will result in this error.

t = datetime('now')

t = datetime
   13-Oct-2021 21:09:06

month(t)

ans = 10

% the error you are seeing due to calling the function without inputs
month

Error using month (line 44)
Please enter D.