forcing the final column in a matrix to be zero

I want to make the final column to go to zero once I go past a certain flag number

k = 10
a = zeros(1:k)
if b < 1
    a = (end 0)
end

I think it looks something like this but I know it isn't exactly right

please help

Alex

Answer 1

[VBBV]

k = 10

k = 10

a = ones(3,k)

a = 3×10

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

b = -1;
if b < 1
    a(:,end) = 0;
end
a

a = 3×10

1 1 1 1 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 0

[A Poyser]

nice thanks