IFFT operation on the vector

Hello,

I want to make an ifft operation on some vector. according to help of ifft, it do not require any multipcation constant. does this statement true all the time?

Answer 1

[Wayne King]

As long as you do not zero pad, you should get back the original vector without using any scaling factor.

   x = randn(10,1);
   xdft = fft(x);
   y = ifft(xdft);
   max(abs(x-y))

Answer 2

[Michael Adelman]

and if I zero pad, what constant I need to multiply?

[Wayne King]

Nothing, it will just add zeros at the end.

   x = randn(10,1);
   xdft = fft(x,16);
   ifft(xdft)