About the usage of for, while and return

I need to perform while loop many times as follows;

data=xlsread('data.xlsx','B1:B86640');
% first part
i_1=1;
while (abs(data(1)) > 0.10 || abs(data(2)) > 0.10 || abs(data(3)) > 0.10)
  i_1=i_1+1;
  if i_1==361;
    errordlg('iteration cannot be converged', 'Error!', 'modal')
    return   
  end
end
% second part
i_2=1;
while (abs(data(362)) > 0.10 || abs(data(363)) > 0.10 || abs(data(364)) > 0.10)
  i_2=i_2+1;
  if i_2==361;
    errordlg('iteration cannot be converged', 'Error!', 'modal')
   return  
  end
end
%third part
i_3=1;
while (abs(data(723)) > 0.10 || abs(data(724)) > 0.10 || abs(data(725)) > 0.10)
  i_3=i_3+1;
  if i_3==361;
    errordlg('iteration cannot be converged', 'Error!', 'modal')
    return  
  end
end

After these excecutions, I need to store i_1, i_2 and i_3 arrays.

% for all abs(data(xx)) parts, xx equals to array of 1:361:86280;

How can I execute the above steps avoiding the repeated parts using a single part of different codes?

[Bjarke Skogstad Larsen]

I think you have a mistake in your code... the expression for stopping the while loops are constant.

What I mean is that you check the same numbers for each iteration of the loop, fx. in the first loop abs(data(1)) > 0.1

Maybe you meant to have it check abs(data(i_1)) > 0.1 or something similar?

[dpb]

Are the calculations for the sections the same just testing the different area within the data array or are the calculations different as well?

At the present we can't see what would change anything inside the loop.

As for

% for all abs(data(xx)) parts, xx equals to array of 1:361:86280;

if xx = data(1:361:86280), then xx has 240 elements ==>

>> 86280/361
ans =
        239
>> 

plus 1 for the start/end points over 239 intervals.

One simplification would be could write

(abs(data(723)) > 0.10 || abs(data(724)) > 0.10 || abs(data(725) > 0.10

as

IDX=723;
TOL=0.10;
any(abs(data(IDX:IDX+2))>TOL)

[sermet OGUTCU]

Larsen, I corrected the parentheses error. I executed the codes and It works what it supposed to be. Of course, I need to execute each part seperately if return condition happens.

[sermet OGUTCU]

@dpv, yes, the calculations for the sections the same just testing the different area within the data array.

[dpb]

In that case, just write an indexing vector and group the entire lot---

Answer 1

[dpb]

With the clarification that operations are the same, then

data=xlsread('data.xlsx','B1:B86640');
% preliminaries -- define stopping criteria data points
N=2;                            % number consecutive points from 
IDX=[1:361:723];                % starting points
TOL=0.10;                       % tolerance
idxvec=cell2mat(arrayfun(@(ix) colon(ix,ix+N),IDX,'UniformOutput',false)); % expand indices to vector
MAXITER = 361;
iter=0;
while any(abs(data(idxvec)>TOL)
  iter=iter+1;
  if iter>=MAXITER
    errordlg('iteration cannot be converged', 'Error!', 'modal')
    return   
  end
  data=yourfunctionthatchangesdatagoeshere(iter,data);   %  do whatever it is need to do...
end