四點快速富利葉轉換(FFT)
程式編寫日期: 2006年7月10日
注意: πr 是按 Shift EXP Shift Ans 2
程式 (71 bytes)
Mem clear: ?→A: ?→B: ?→C: ?→D:
Lbl 0: πr M÷2→X: A + B cos X + C cos2X + D cos3X◢
- B sinX - C sin 2X - D sin 3X◢ 1M+: M - 4 => Goto 0: Norm 1
Example: Perform a 4-sample FFT for the input sequence x[n]={ 1, 0, 3, 1}
Press Prog 1 1 EXE 0 EXE 3 EXE 1 EXE (read-out: 5) EXE (read-out: 0)
EXE (read-out: -2) EXE (read-out: 1)
EXE (read-out: 3) EXE (read-out: 0)
EXE (read-out: -2) EXE (read-out: -1)
Therefore, the result is:
X[0] = 5
X[1] = - 2 + j
X[2] = 3
X[3] = - 2 - j