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update Octave Project Developers copyright for the new year In files that have the "Octave Project Developers" copyright notice, update for 2021.
author John W. Eaton <jwe@octave.org>
date Wed, 10 Feb 2021 09:52:15 -0500
parents bd51beb6205e
children 32c3a5805893
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1 ////////////////////////////////////////////////////////////////////////
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2 //
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3 // Copyright (C) 2004-2021 The Octave Project Developers
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4 //
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5 // See the file COPYRIGHT.md in the top-level directory of this
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6 // distribution or <https://octave.org/copyright/>.
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7 //
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8 // This file is part of Octave.
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9 //
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10 // Octave is free software: you can redistribute it and/or modify it
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11 // under the terms of the GNU General Public License as published by
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12 // the Free Software Foundation, either version 3 of the License, or
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13 // (at your option) any later version.
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14 //
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15 // Octave is distributed in the hope that it will be useful, but
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16 // WITHOUT ANY WARRANTY; without even the implied warranty of
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17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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18 // GNU General Public License for more details.
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19 //
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20 // You should have received a copy of the GNU General Public License
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21 // along with Octave; see the file COPYING. If not, see
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22 // <https://www.gnu.org/licenses/>.
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23 //
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24 ////////////////////////////////////////////////////////////////////////
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25
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26 #if defined (HAVE_CONFIG_H)
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27 # include "config.h"
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28 #endif
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29
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30 #include "lo-mappers.h"
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31
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32 #include "defun.h"
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33 #include "error.h"
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34 #include "errwarn.h"
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35 #include "ovl.h"
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36 #include "utils.h"
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37
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38 // This function should be merged with Fifft.
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39
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40 static octave_value
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41 do_fftn (const octave_value_list& args, const char *fcn, int type)
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42 {
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43 int nargin = args.length ();
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44
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45 if (nargin < 1 || nargin > 2)
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46 print_usage ();
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47
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48 octave_value retval;
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49 octave_value arg = args(0);
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50 dim_vector dims = arg.dims ();
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51
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52 for (int i = 0; i < dims.ndims (); i++)
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53 if (dims(i) < 0)
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54 return retval;
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55
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56 if (nargin > 1)
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57 {
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58 Matrix val = args(1).xmatrix_value ("%s: SIZE must be a vector of length dim", fcn);
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59
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60 if (val.rows () > val.columns ())
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61 val = val.transpose ();
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62
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63 if (val.columns () != dims.ndims () || val.rows () != 1)
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64 error ("%s: SIZE must be a vector of length dim", fcn);
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65
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66 for (int i = 0; i < dims.ndims (); i++)
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67 {
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68 if (octave::math::isnan (val(i,0)))
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69 error ("%s: SIZE has invalid NaN entries", fcn);
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70 else if (octave::math::nint_big (val(i,0)) < 0)
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71 error ("%s: all dimensions in SIZE must be greater than zero", fcn);
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72 else
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73 dims(i) = octave::math::nint_big(val(i,0));
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74 }
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75 }
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76
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77 if (dims.all_zero ())
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78 {
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79 if (arg.is_single_type ())
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80 return octave_value (FloatMatrix ());
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81 else
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82 return octave_value (Matrix ());
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83 }
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84
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85 if (arg.is_single_type ())
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86 {
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87 if (arg.isreal ())
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88 {
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89 FloatNDArray nda = arg.float_array_value ();
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90
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91 nda.resize (dims, 0.0);
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92 retval = (type != 0 ? nda.ifourierNd () : nda.fourierNd ());
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93 }
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94 else
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95 {
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96 FloatComplexNDArray cnda = arg.float_complex_array_value ();
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97
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98 cnda.resize (dims, 0.0);
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99 retval = (type != 0 ? cnda.ifourierNd () : cnda.fourierNd ());
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100 }
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101 }
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102 else
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103 {
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104 if (arg.isreal ())
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105 {
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106 NDArray nda = arg.array_value ();
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107
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108 nda.resize (dims, 0.0);
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109 retval = (type != 0 ? nda.ifourierNd () : nda.fourierNd ());
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110 }
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111 else if (arg.iscomplex ())
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112 {
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113 ComplexNDArray cnda = arg.complex_array_value ();
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114
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115 cnda.resize (dims, 0.0);
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116 retval = (type != 0 ? cnda.ifourierNd () : cnda.fourierNd ());
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117 }
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118 else
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119 err_wrong_type_arg (fcn, arg);
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120 }
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121
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122 return retval;
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123 }
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124
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125 DEFUN (fftn, args, ,
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126 doc: /* -*- texinfo -*-
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127 @deftypefn {} {} fftn (@var{A})
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128 @deftypefnx {} {} fftn (@var{A}, @var{size})
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129 Compute the N-dimensional discrete Fourier transform of @var{A} using
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130 a Fast Fourier Transform (FFT) algorithm.
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131
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132 The optional vector argument @var{size} may be used specify the dimensions
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133 of the array to be used. If an element of @var{size} is smaller than the
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134 corresponding dimension of @var{A}, then the dimension of @var{A} is
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135 truncated prior to performing the FFT@. Otherwise, if an element of
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136 @var{size} is larger than the corresponding dimension then @var{A} is
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137 resized and padded with zeros.
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138 @seealso{ifftn, fft, fft2, fftw}
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139 @end deftypefn */)
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140 {
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141 return do_fftn (args, "fftn", 0);
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142 }
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143
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144 DEFUN (ifftn, args, ,
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145 doc: /* -*- texinfo -*-
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146 @deftypefn {} {} ifftn (@var{A})
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147 @deftypefnx {} {} ifftn (@var{A}, @var{size})
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148 Compute the inverse N-dimensional discrete Fourier transform of @var{A}
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149 using a Fast Fourier Transform (FFT) algorithm.
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150
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151 The optional vector argument @var{size} may be used specify the dimensions
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152 of the array to be used. If an element of @var{size} is smaller than the
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153 corresponding dimension of @var{A}, then the dimension of @var{A} is
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154 truncated prior to performing the inverse FFT@. Otherwise, if an element of
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155 @var{size} is larger than the corresponding dimension then @var{A} is
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156 resized and padded with zeros.
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157 @seealso{fftn, ifft, ifft2, fftw}
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158 @end deftypefn */)
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159 {
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160 return do_fftn (args, "ifftn", 1);
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161 }