Mercurial > octave
view libinterp/corefcn/fft2.cc @ 20918:6f0bd96f93c0
maint: Use new C++ archetype in more files.
Place input validation first in files.
Move declaration of retval down in function to be closer to point of usage.
Eliminate else clause after if () error.
Use "return ovl()" where it makes sense.
* __dispatch__.cc, __dsearchn__.cc, __ichol__.cc, __lin_interpn__.cc,
balance.cc, betainc.cc, bitfcns.cc, bsxfun.cc, cellfun.cc, colloc.cc, conv2.cc,
daspk.cc, dasrt.cc, dassl.cc, data.cc, debug.cc, dirfns.cc, dlmread.cc, dot.cc,
eig.cc, error.cc, fft.cc, fft2.cc, fftn.cc, file-io.cc, ov-type-conv.h:
Use new C++ archetype in more files.
author | Rik <rik@octave.org> |
---|---|
date | Wed, 16 Dec 2015 15:00:31 -0800 |
parents | 1142cf6abc0d |
children | 48b2ad5ee801 |
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/* Copyright (C) 1997-2015 David Bateman Copyright (C) 1996-1997 John W. Eaton This file is part of Octave. Octave is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. Octave is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Octave; see the file COPYING. If not, see <http://www.gnu.org/licenses/>. */ #ifdef HAVE_CONFIG_H #include <config.h> #endif #include "lo-mappers.h" #include "defun.h" #include "error.h" #include "gripes.h" #include "oct-obj.h" #include "utils.h" // This function should be merged with Fifft. #if defined (HAVE_FFTW) #define FFTSRC "@sc{fftw}" #else #define FFTSRC "@sc{fftpack}" #endif static octave_value do_fft2 (const octave_value_list &args, const char *fcn, int type) { int nargin = args.length (); if (nargin < 1 || nargin > 3) print_usage (); octave_value retval; octave_value arg = args(0); dim_vector dims = arg.dims (); octave_idx_type n_rows = -1; if (nargin > 1) { double dval = args(1).double_value (); if (xisnan (dval)) error ("%s: number of rows (N) cannot be NaN", fcn); n_rows = NINTbig (dval); if (n_rows < 0) error ("%s: number of rows (N) must be greater than zero", fcn); } octave_idx_type n_cols = -1; if (nargin > 2) { double dval = args(2).double_value (); if (xisnan (dval)) error ("%s: number of columns (M) cannot be NaN", fcn); n_cols = NINTbig (dval); if (n_cols < 0) error ("%s: number of columns (M) must be greater than zero", fcn); } for (int i = 0; i < dims.length (); i++) if (dims(i) < 0) return retval; if (n_rows < 0) n_rows = dims(0); else dims(0) = n_rows; if (n_cols < 0) n_cols = dims(1); else dims(1) = n_cols; if (dims.all_zero () || n_rows == 0 || n_cols == 0) { if (arg.is_single_type ()) return octave_value (FloatMatrix ()); else return octave_value (Matrix ()); } if (arg.is_single_type ()) { if (arg.is_real_type ()) { FloatNDArray nda = arg.float_array_value (); nda.resize (dims, 0.0); retval = (type != 0 ? nda.ifourier2d () : nda.fourier2d ()); } else { FloatComplexNDArray cnda = arg.float_complex_array_value (); cnda.resize (dims, 0.0); retval = (type != 0 ? cnda.ifourier2d () : cnda.fourier2d ()); } } else { if (arg.is_real_type ()) { NDArray nda = arg.array_value (); nda.resize (dims, 0.0); retval = (type != 0 ? nda.ifourier2d () : nda.fourier2d ()); } else if (arg.is_complex_type ()) { ComplexNDArray cnda = arg.complex_array_value (); cnda.resize (dims, 0.0); retval = (type != 0 ? cnda.ifourier2d () : cnda.fourier2d ()); } else gripe_wrong_type_arg (fcn, arg); } return retval; } DEFUN (fft2, args, , "-*- texinfo -*-\n\ @deftypefn {} {} fft2 (@var{A})\n\ @deftypefnx {} {} fft2 (@var{A}, @var{m}, @var{n})\n\ Compute the two-dimensional discrete Fourier transform of @var{A} using\n\ a Fast Fourier Transform (FFT) algorithm.\n\ \n\ The optional arguments @var{m} and @var{n} may be used specify the number of\n\ rows and columns of @var{A} to use. If either of these is larger than the\n\ size of @var{A}, @var{A} is resized and padded with zeros.\n\ \n\ If @var{A} is a multi-dimensional matrix, each two-dimensional sub-matrix\n\ of @var{A} is treated separately.\n\ @seealso{ifft2, fft, fftn, fftw}\n\ @end deftypefn") { return do_fft2 (args, "fft2", 0); } DEFUN (ifft2, args, , "-*- texinfo -*-\n\ @deftypefn {} {} ifft2 (@var{A})\n\ @deftypefnx {} {} ifft2 (@var{A}, @var{m}, @var{n})\n\ Compute the inverse two-dimensional discrete Fourier transform of @var{A}\n\ using a Fast Fourier Transform (FFT) algorithm.\n\ \n\ The optional arguments @var{m} and @var{n} may be used specify the number of\n\ rows and columns of @var{A} to use. If either of these is larger than the\n\ size of @var{A}, @var{A} is resized and padded with zeros.\n\ \n\ If @var{A} is a multi-dimensional matrix, each two-dimensional sub-matrix\n\ of @var{A} is treated separately\n\ @seealso{fft2, ifft, ifftn, fftw}\n\ @end deftypefn") { return do_fft2 (args, "ifft2", 1); } /* %% Author: David Billinghurst (David.Billinghurst@riotinto.com.au) %% Comalco Research and Technology %% 02 May 2000 %!test %! M = 16; %! N = 8; %! %! m = 5; %! n = 3; %! %! x = 2*pi*(0:1:M-1)/M; %! y = 2*pi*(0:1:N-1)/N; %! sx = cos (m*x); %! sy = sin (n*y); %! s = kron (sx',sy); %! S = fft2 (s); %! answer = kron (fft (sx)', fft (sy)); %! assert (S, answer, 4*M*N*eps); %% Author: David Billinghurst (David.Billinghurst@riotinto.com.au) %% Comalco Research and Technology %% 02 May 2000 %!test %! M = 12; %! N = 7; %! %! m = 3; %! n = 2; %! %! x = 2*pi*(0:1:M-1)/M; %! y = 2*pi*(0:1:N-1)/N; %! %! sx = cos (m*x); %! sy = cos (n*y); %! %! S = kron (fft (sx)', fft (sy)); %! answer = kron (sx', sy); %! s = ifft2 (S); %! %! assert (s, answer, 30*eps); %% Author: David Billinghurst (David.Billinghurst@riotinto.com.au) %% Comalco Research and Technology %% 02 May 2000 %!test %! M = 16; %! N = 8; %! %! m = 5; %! n = 3; %! %! x = 2*pi*(0:1:M-1)/M; %! y = 2*pi*(0:1:N-1)/N; %! sx = single (cos (m*x)); %! sy = single (sin (n*y)); %! s = kron (sx', sy); %! S = fft2 (s); %! answer = kron (fft (sx)', fft (sy)); %! assert (S, answer, 4*M*N*eps ("single")); %% Author: David Billinghurst (David.Billinghurst@riotinto.com.au) %% Comalco Research and Technology %% 02 May 2000 %!test %! M = 12; %! N = 7; %! %! m = 3; %! n = 2; %! %! x = single (2*pi*(0:1:M-1)/M); %! y = single (2*pi*(0:1:N-1)/N); %! %! sx = cos (m*x); %! sy = cos (n*y); %! %! S = kron (fft (sx)', fft (sy)); %! answer = kron (sx', sy); %! s = ifft2 (S); %! %! assert (s, answer, 30*eps ("single")); */