Changing Values in a column due to another value

I have a collumn which contains 0s and 1s. The value 1 indicates that a failure occurred. I want to change the previous 6 rows prior to the failure to 1s also.

Does anyone have any idea about the best method to do this?

Answer 1

[Dyuman Joshi]

i = find(c==1,1,'first');       %c is the column vector
if i>6
    c(i-6:i-1)=1;
else 
    c(1:i-1)=1;
end