How to find a value that is close to the gap?

L=50;
dx=5;
Xp = L/dx;
Xs=8
start=0;
eend=dx;
for n=1:Xp

      if Xs>=start && Xs<=eend
          start = eend;
      else
          eend = eend*n;
      end
  end
                                         n= 0 1 2  3   4  5  6  7  8  9  10

The problem is there are 50/5=25 gaps, from 0 5 10 15 20 25 30 35 40 45 50, and I want to find the one that is near Xs. From the above, Xs=8 so it is closer to 10. I want to find the number of n. What went wrong with my code?

Answer 1

[Walter Roberson]

t = start : dx : L;
n = 0:length(t)-1;
n_val = interp1( t, n, Xs, 'nearest');

Cross-check:

t(n_val == n)