How to specify a variable (using linspace) like this?

Distance between first and second point and the distance between second last and last point is 0.5h. All other distances between the neighboring points is h. How to create a grid of say N points that do not include the first and the last point in the grid?

Answer 1

[Andrei Bobrov]

afirst = 2;
h = .5;
N = 5;
out = afirst + cumsum([0, .5*h,ones(1,N-1)*h,.5*h])

or

out = [afirst,linspace(afirst + .5*h,afirst + .5*h + (N-1)*h,N),afirst + N*h];

or

a = [2 6];
N = 5;
L = linspace(a(1),a(2),N+1)
L(2:end) = L(2:end)-diff(a)/N*.5
out = [L,a(end)];

[Taha]

He has asked "do not include the first and the last point". I think your solutions include the first and last points.

[Shashank]

Thanks Andrei. You seem to have given me a lot of options. I think the second one looks more cogent.

Answer 2

[Taha]

N = 5;
h = (last - first)/N;
grid = linspace(first+h/2, last-h/2, N);

[Shashank]

So if I need to call a matrix, say A = f(1) + f(3), how should I do it using your method? And should I specify the values of "first" and "last" as the end points of my domain?

[Taha]

The above piece of code needs 'N', 'last', and 'first' as input parameters. Also, I didn't get what you mean by 'calling a matrix'.