executing for loop from 1 to n except one number

I have a specific number, for example row=3; and I have a for like:

 for i=1:n
    SOMETHING
 end

and n is a matrix's row number, I need to do something in this for, and it should be done on all indexes except the one that is determined in row=3. I mean I want to do something on all 1 to n and not for 3. how can I do this?

Answer 1

[Walter Roberson]

for i = setdiff(1:n, row)
  SOMETHING
end

In this code, row could be a row vector if you wanted to exclude multiple values

[negin tebyani]

thanks