176177178179180181182183184185186
DoubleFFT_1D fft = CACHE_1D.get(n); if (fft == null) { fft = new DoubleFFT_1D(n); CACHE_1D.put(n, fft); } fft.realForward(a); return unpack(a); } /** * The backward discrete Fourier transform. *Note:* In this definition $i$