You need to tell it either one row or one column. Try this:
inc = [10000, 20000 30000, 40000, 50000, 60000, 70000, 80000, 90000, 100000];
maxValue = 100000;
for k = 1 : length(inc)
vec1 = randi(maxValue, 1, inc(k));
fprintf('Made a vector with %d rows and %d columns.\n', size(vec1, 1), size(vec1, 2));
end
Best Answer