friend pvector J(const pvector& in1)Return value:
- pvector J: Inverse Discrete Fourier Transform (DFT) of in1
Input:
- in1: pvector
Using the code provided in the appendix for I(..), write a function of the above prototype to perform the inverse Fourier transform. To debug, uncomment the ``Tests of J and I'' and run the program.
Hint: To get J() to be the inverse of I(), don't forget the
normalization by 
where the box dimensions are
accessible through in1.N.x, in1.N.y and in1.N.z. Also, don't forget
to switch the sign of i in the transform!