Unrecognized variable x error

for k=n-1:1
      x(n)=cnew(n)/dnew(n)
      x(k)=(cnew(k)-a(k)*x(k+1))/d(k)
 end
 Tnew(i,j)=x(i)

P.S. cnew and all others are known.

Still while running this i am getting an error-

Unrecognized function or variable 'x'.
Error in ADI (line 51)
        Tnew(i,j)=x(i)

Answer 1

[Cris LaPierre]

What is the value of n?

The most obvious thing to me is that your for loop doesn't actually run, so x is never created.

The loops don't run because you start at k=n-1 and ends when k=1. You're not getting an error that your index has to be positive, so n>=2. If x is not created at all, that means n>=3, causing to loop indices to be 2:1, resulting in an empty array, which means your loop never runs.

[ravi shukla]

i think to add step -1.

for k=n-1:-1:1

this will resolve my issue..say n=5

so k=4:-1:1

4

3

2

1