已知https://bgk-photo.cdn.bcebos.com/4a36acaf2edda3cc8202e74111e93901203f92e9.jpg是N点有限长序列,https://bgk-photo.cdn.bcebos.com/8435e5dde71190ef661acdbede1b9d16fcfa60e9.jpg。现将长度变成https://bgk-photo.cdn.bcebos.com/35a85edf8db1cb136cef6372cd54564e93584bc8.jpg点的有限长序列https://bgk-photo.cdn.bcebos.com/c2cec3fdfc0392458554be6e9794a4c27c1e25e9.jpghttps://bgk-photo.cdn.bcebos.com/5366d0160924ab18f2f7be5625fae6cd7a890be9.jpg https://bgk-photo.cdn.bcebos.com/962bd40735fae6cd1232f4001fb30f2443a70fc8.jpg试求https://bgk-photo.cdn.bcebos.com/4afbfbedab64034f034b9d67bfc379310b551dc8.jpg点DFT[https://bgk-photo.cdn.bcebos.com/b8014a90f603738d25cc5343a31bb051f919ecc9.jpg]与https://bgk-photo.cdn.bcebos.com/060828381f30e9241922c3505c086e061c95f7c9.jpg的关系。