how to create a vector with certain range of values

how can i create a vector where i chose that the first n numbers in the vector is 0 and then from n+1 the values are 1 to end. example if n =3 and the vector is 10 long then it would be [0 0 0 1 1 1 1 1 1 1]. or if n = 2 than [0 0 1 1 1 1 1 1 1 1]. i will be using this on a vector that is 1X250 and is changing the n 250 times in a for loop.

Answer 1

[Chad Greene]

There should be no need for a loop. Enter any value for n:

n = 3; 
v = zeros(1,250); 
v(n+1:end) = 1;

Answer 2

[Walter Roberson]

[zeros(1,n),ones(1,TheLength - n)]

However if this is in a "for" loop and you are certain that the loop is being run in order, then

V = ones(1,TheLength);

for n = 1 : TheLength
  V(n) = 0;
  ...
end

this zeros one more entry every iteration, which is less work than building a new vector