How can I write dft code from k = -3 ~ 3 for A = [1 7 5 11 15 19 8]?

I must use k = -3 ~ 3 in my code.

[José-Luis]

What does

 k = -3 ~ 3

mean?

[Parisa PASHA]

For given k = -3 ~ 3, perform discrete Fourier transform to the follow array:

A = [1 7 5 11 15 19 8]

[Parisa PASHA]

In Discrete Fourier Transform K=0:N-1 but I need to write a code in different way from K=-3:3.

[Parisa PASHA]

It must be something like this:

x = [1 7 5 11 15 19 8];

N = length(x);

for k = -3:1:3

         for n = 1:N

          X(:,n) = exp(-2*pi*1i*n*k./N);

      end
  end
  X

Answer 1

[Pritesh Shah]

It should be -3:3

[Parisa PASHA]

But when I use k=-3:3 the error appear like this Attempted to access (-3); index must be a positive integer or logical.