I ran through this for one column. A while-loop worked for me
The basic algorithm is:
- Generate a random index
- Check if the index is valid, i.e., it is not already set to NaN and doesn't have a consecutive one already added
- If valid, set that element to NaN
- Else, regenerate another index
- Keep going until the number of NaNs is 10
a = randn(100,1);
numElems = size(a,1);
numNans = numElems*0.1; % Number of NaNs is 10%
count = 1;
while count <= numNans
% Generate random number
idx = randi(numElems);
isIdxValid = false;
if ~isnan(a(idx)) % Check if index has already been set
% Check for NaNs in consecutive locations
if idx==1 % beginning of vector
if ~isnan(a(idx+1))
isIdxValid = true;
end
elseif idx==numElems % end of vector
if ~isnan(a(idx-1))
isIdxValid = true;
end
else % middle of vector
if ~isnan(a(idx+1)) && ~isnan(a(idx-1))
isIdxValid = true;
end
end
end
% If the index is valid, set that element to NaN
if isIdxValid
a(idx) = NaN;
count = count+1;
end
end
% Display stuff at the end
a
nnz(isnan(a))
