index = 0

[Francesco Potorti`]

>I have an array V(1,N) . I am running some operation where I need to
>declare two boundary conditions at V(0) and V(N+1). 

Octave's arrays are 1-based.  The index always starts at 1 and goes up.
So you cannot access or set the V(0) element, as it does not exist.
Moreover, if your array has length N, you cannot access element V(N+1),
as it does not exist either.

>To do this I declared V= zeros(0,N+1).

If you want a row array (that is, 1 row and N columns) filled with
zeros, you create it with V=zeros(1,N);.

What you did creates an empty array (one with 0 rows).

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