impemented FFT with numpy and recursion

FFT.py

@@ -20,12 +20,15 @@ def FFT_real(inp):
 
 
 def FFT(inp):
+  return FFT_np(inp)
+
+def FFT_np(inp):
   inp = np.array(inp)
   N = inp.shape[0]
   if N == 1:
     return inp
-  X_even = FFT(inp[::2])
-  X_odd  = FFT(inp[1::2])
+  X_even = FFT_np(inp[::2])
+  X_odd  = FFT_np(inp[1::2])
   k = np.arange(N // 2)
   tw = np.exp(-2j * np.pi * k / N) * X_odd
   return np.concatenate((X_even + tw, X_even - tw))