I'm trying to understand some optimizations on DFT. So in this step, there is a note like the following:
The next step involves the mathematical observation that the even-numbered elements can be computed separately from the odd ones. In cases where n is even, this will reduce the number of multiplications by half.
And this is the formula for even part:
Sorry for this newbie question but I have watched several videos, read a number of papers but still don't get how the "sum[k]" is generated.
btw: m is N/2