how to make a funcation that return smallest posible integer from series

Hi everyone; I am going to attempt query. Function called one_per_n that returns the smallest positive integer n for which the sum 1 + 1/2 + 1/3 + … + 1/n , is greater than or equal to x where x is the input argument. Limit the maximum number n of terms in the sum to 10,000 and return -1 if it is exceeded. (Note: if your program or the grader takes a long time, you may have created an infinite loop and need to hit Ctrl-­‐ C on your keyboard.) I am using that code

function out=one_per_n(x)
total=0;
for n=1:10000
  total=total+1/n;
  if total>=x
    break ;
  end
end
out=n;
end

But when i run this for grader i got an error like this

Feedback: Your function performed correctly for argument(s) 1
    Feedback: Your function performed correctly for argument(s) 2
    Feedback: Your function performed correctly for argument(s) 3
    Feedback: Your function performed correctly for argument(s) 4
    Feedback: Your function performed correctly for argument(s) 8
    Feedback: Your function performed correctly for argument(s) 9
    Feedback: Your function performed correctly for argument(s) 9.7875
    Feedback: Your function performed correctly for argument(s) 9.7876
    Feedback: Your function made an error for argument(s) 9.7877

      Your solution is _not_ correct.

Guide me where i need correction in my code to resolve this error.. Thanks in advance

Answer 1

[Thorsten]

You forgot to handle the -1 case:

function out = one_per_n(x)
total = 0; found = 0;
for n = 1:10000
  total = total+1/n;
  if total >= x
    out = n ; found = 1; break
  end
end
if ~found
  out = -1;
end
end

[Muhammad Usman Saleem]

@ Thorsten thanks..