Unable to perform assignment because the left and right sides have a different number of elements

When there are no values ​​less than 100 in my matrix, this error appears

for i=1:length(NpingZ) 
x=find(Mdata(1:VecA(i),i)<100,1,'last')';
Data(i)=x; 
end

Is there a way to fix this error?

I will be glad to any advice

Answer 1

[Jan]

Data = nan(1, length(NpingZ));  % Pre-allocate and default value
for i=1:length(NpingZ) 
  x = find(Mdata(1:VecA(i), i) < 100, 1, 'last')';
  if ~isempty(x)
    Data(i) = x; 
  end
end