def nufft1d3(x, c, isign, eps, s, f, debug=0, spread_debug=0, spread_sort=2, fftw=0, upsampfac=2.0): """1D type-3 (NU-to-NU) complex nonuniform fast Fourier transform :: nj-1 f[k] = SUM c[j] exp(+-i s[k] x[j]), for k = 0, ..., nk-1 j=0 Args: x (float[nj]): nonuniform source points, in R c (complex[nj]): source strengths isign (int): if >=0, uses + sign in exponential, otherwise - sign eps (float): precision requested (>1e-16) s (float[nk]): nonuniform target frequency points, in R f (complex[nk]): output values at target frequencies. Should be initialized as a numpy array of the correct size debug (int, optional): 0 (silent), 1 (print timing breakdown) spread_debug (int, optional): 0 (silent), 1, 2... (print spreader info) spread_sort (int, optional): 0 (don't sort NU pts in spreader), 1 (sort), 2 (heuristic decision to sort) fftw (int, optional): 0 (use FFTW_ESTIMATE), 1 (use FFTW_MEASURE) upsampfac (float): either 2.0 (default), or 1.25 (low RAM & small FFT size) .. note:: The output is written into the f array. Returns: int: 0 if success, 1 if eps too small, 2 if size of arrays to malloc exceed MAX_NF Example: see ``python_tests/accuracy_speed_tests.py`` """ # f is the output and must have dtype=np.complex128 x = x.astype(np.float64, copy=False) #copies only if type changes c = c.astype(np.complex128, copy=False) #copies only if type changes s = s.astype(np.float64, copy=False) #copies only if type changes return finufftpy_cpp.finufft1d3_cpp(x, c, isign, eps, s, f, debug, spread_debug, spread_sort, fftw, upsampfac)
def finufft1d3(x, c, isign, eps, s, f, debug=0, spread_debug=0, spread_sort=1, fftw=0): """1D type-3 (NU-to-NU) complex nonuniform fast Fourier transform nj f[k] = SUM c[j] exp(+-i s[k] x[j]), for k = 1, ..., nk j=1 Inputs: x (float[nj]): nonuniform source points, in R c (complex[nj]): source strengths s (float[nk]): nonuniform target frequency points, in R isign (int): if >=0, uses + sign in exponential, otherwise - sign. eps (float): precision requested (>1e-16) Optional inputs: debug (int): 0 (silent), 1 (print timing breakdown). spread_debug (int): 0 (spreader silent), 1, 2... (print spreader info) spread_sort (int): 0 (don't sort NU pts in spreader), 1 (sort) fftw (int): 0 (use FFTW_ESTIMATE), 1 (use FFTW_MEASURE), ... Outputs: f (complex[nk]): values at target frequencies Returns: error status, 0 : success 1 : eps too small 2 : size of arrays to malloc exceed MAX_NF Example: see python_tests/accuracy_speed_tests.py """ # f is the output and must have dtype=np.complex128 x = x.astype(np.float64, copy=False) #copies only if type changes c = c.astype(np.complex128, copy=False) #copies only if type changes s = s.astype(np.float64, copy=False) #copies only if type changes return finufftpy_cpp.finufft1d3_cpp(x, c, isign, eps, s, f, debug, spread_debug, spread_sort, fftw)