How to use for loop rather than nesting if loop

I want to use this code to subtract one value from each number in the histogram when all have been selected to find the new number with zero counts. This code worked (since there are two if loops with one nested) for the first two times 1 is subtracted from cdiff, but then returns the error 'Unbalanced or unexpected parenthesis or bracket.' : %check if Cdiff is empty:

if isempty(C_diff)
    fprintf('C_diff is empty (all numbers have drawn once) \n');
    cdiff_counts= counts - 1;%cdiff_data_vector = reshape(data,[9,numel(data)]); 
    C_diff = find(cdiff_counts==0);%return vector of values with 0
    fprintf('By subtracting 1 count for all numbers, the new C_diff is %d\n', C_diff);
    if isempty(C_diff)
        fprintf('C_diff is empty (all numbers have drawn once) \n');
        cdiff_counts= cdiff_counts - 1;%cdiff_data_vector = reshape(data,[9,numel(data)]); 
        C_diff = find(cdiff_counts==0);%return vector of values with 0
        fprintf('By subtracting 1 count for all numbers, the new C_diff is %d\n', C_diff);
    end
else
  fprintf('C_diff is %d\n', C_diff);%
end
Replacing the first 'if' with 'for' returns 'Unbalanced or unexpected parenthesis or bracket.'

How can I get this to occur until C_diff is no longer an empty array?

if isempty(C_diff)
      fprintf('C_diff is empty (all numbers have drawn once) \n');
      cdiff_counts= counts - 1;%cdiff_data_vector = reshape(data,[9,numel(data)]); 
      C_diff = find(cdiff_counts==0);%return vector of values with 0
      fprintf('By subtracting 1 count for all numbers, the new C_diff is %d\n', C_diff);
  else
    fprintf('C_diff is %d\n', C_diff);%
  end

Best regards,

Alex

[Jan]

There are no "if loops" in any programming language.

[Alex]

ok, "if statement"?

Answer 1

[Jan]

while isempty(C_diff)
  cdiff_counts = counts - 1;
  C_diff       = find(cdiff_counts == 0);
end

It looks like C_diff contains positive values initially, maybe only integers. Then this is more efficient:

minValue = min(counts);     % [EDITED]
C_diff   = find(C_diff = minValue);

[Alex]

This answer helped, but did not work because in the first if statement cdiff_counts = counts -1, then in subsequently nested statements cdiff_counts = cdiff_counts -1. Here is what worked:

%C_diff
il=1;
while isempty(C_diff)
  fprintf('C_diff is empty (all numbers have drawn once) \n');
  cdiff_counts = counts - il;
  C_diff       = find(cdiff_counts == 0);
  il=il+1;
end
fprintf('C_diff is %d\n', C_diff);%

Thank you nevertheless!

[Jan]

I had a typo in the min() call. I assume, it is much cheaper. If you provide some meaningful inputs data and the wanted result, I could even test my suggestions.

[Alex]

Thank you! I will keep that in mind for future questions. It is not necessary, but if you are interested, here is the "counts" data for numbers 1:1:49. The number 32 should be returned.