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view scripts/signal/fftfilt.m @ 28789:28de41192f3c
Eliminate unneeded verification of nargin, nargout in m-files.
* FIRfilter.m, FIRfilter_aggregation.m, get.m, polynomial.m,
polynomial_superiorto.m, polynomial2.m, makeUniqueStrings.m, base64decode.m,
base64encode.m, cd.m, lin2mu.m, record.m, sound.m, soundsc.m, accumarray.m,
accumdim.m, bitcmp.m, bitset.m, cart2pol.m, celldisp.m, circshift.m,
cplxpair.m, cumtrapz.m, flip.m, idivide.m, interpft.m, logspace.m, pol2cart.m,
polyarea.m, postpad.m, prepad.m, rat.m, rot90.m, rotdim.m, shift.m, shiftdim.m,
sortrows.m, trapz.m, dsearch.m, dsearchn.m, getappdata.m, getpixelposition.m,
guidata.m, guihandles.m, isappdata.m, listfonts.m, uigetdir.m,
waitforbuttonpress.m, __makeinfo__.m, doc.m, get_first_help_sentence.m,
autumn.m, bone.m, brighten.m, cmpermute.m, cmunique.m, colorcube.m, contrast.m,
cool.m, copper.m, cubehelix.m, flag.m, gray.m, gray2ind.m, hot.m, hsv.m,
im2double.m, im2frame.m, imformats.m, jet.m, lines.m, ocean.m, pink.m, prism.m,
rainbow.m, rgbplot.m, spinmap.m, spring.m, summer.m, viridis.m, white.m,
winter.m, beep.m, importdata.m, is_valid_file_id.m, javachk.m, javaclasspath.m,
findstr.m, genvarname.m, strmatch.m, bandwidth.m, commutation_matrix.m, cond.m,
cross.m, isdefinite.m, ishermitian.m, issymmetric.m, krylov.m, linsolve.m,
logm.m, lscov.m, null.m, ordeig.m, orth.m, rank.m, rref.m, vecnorm.m,
bunzip2.m, citation.m, computer.m, copyfile.m, dir.m, dos.m, fileattrib.m,
gunzip.m, inputParser.m, inputname.m, ismac.m, ispc.m, isunix.m, license.m,
list_primes.m, methods.m, mkdir.m, movefile.m, nargchk.m, news.m,
orderfields.m, recycle.m, tar.m, unix.m, unpack.m, untar.m, unzip.m, ver.m,
version.m, what.m, zip.m, decic.m, fminbnd.m, fminunc.m, fsolve.m, fzero.m,
glpk.m, humps.m, lsqnonneg.m, optimget.m, pqpnonneg.m, sqp.m, pathdef.m,
camlookat.m, hidden.m, specular.m, plotmatrix.m, smooth3.m, sombrero.m,
stemleaf.m, __gnuplot_drawnow__.m, __opengl_info__.m, ancestor.m, cla.m,
close.m, closereq.m, copyobj.m, gca.m, gcf.m, ginput.m, graphics_toolkit.m,
groot.m, hgload.m, hgsave.m, isgraphics.m, ishold.m, linkaxes.m, meshgrid.m,
newplot.m, refresh.m, refreshdata.m, rotate.m, saveas.m, struct2hdl.m, conv.m,
mkpp.m, mpoles.m, padecoef.m, pchip.m, polyder.m, polyfit.m, polygcd.m,
polyint.m, polyout.m, polyval.m, ppder.m, ppint.m, getpref.m, ispref.m,
rmpref.m, profexport.m, profshow.m, powerset.m, arch_fit.m, arma_rnd.m,
blackman.m, detrend.m, diffpara.m, fftconv.m, fftfilt.m, filter2.m, freqz.m,
freqz_plot.m, hamming.m, hanning.m, sinetone.m, sinewave.m, spectral_adf.m,
spectral_xdf.m, stft.m, unwrap.m, gplot.m, ichol.m, ilu.m, spdiags.m, sprand.m,
sprandn.m, spstats.m, svds.m, treelayout.m, treeplot.m, betainc.m,
betaincinv.m, ellipke.m, gammainc.m, gammaincinv.m, legendre.m, pow2.m,
hankel.m, pascal.m, rosser.m, toeplitz.m, bounds.m, corr.m, cov.m, histc.m,
kendall.m, kurtosis.m, mad.m, mode.m, moment.m, prctile.m, quantile.m, range.m,
ranks.m, run_count.m, skewness.m, spearman.m, std.m, var.m, zscore.m,
dec2base.m, dec2bin.m, dec2hex.m, index.m, mat2str.m, native2unicode.m,
ostrsplit.m, strjoin.m, strjust.m, strtok.m, substr.m, unicode2native.m,
untabify.m, __debug_octave__.m, demo.m, example.m, fail.m, oruntests.m,
dump_demos.m, speed.m, test.m, date.m, datenum.m, datestr.m, datevec.m,
is_leap_year.m, now.m, weekday.m:
Eliminate unneeded verification of nargin, nargout in m-files now that
the interpreter checks these values.
author | Rik <rik@octave.org> |
---|---|
date | Thu, 24 Sep 2020 14:44:58 -0700 |
parents | 9f9ac219896d |
children | d8318c12d903 |
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######################################################################## ## ## Copyright (C) 1994-2020 The Octave Project Developers ## ## See the file COPYRIGHT.md in the top-level directory of this ## distribution or <https://octave.org/copyright/>. ## ## 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 ## <https://www.gnu.org/licenses/>. ## ######################################################################## ## -*- texinfo -*- ## @deftypefn {} {} fftfilt (@var{b}, @var{x}) ## @deftypefnx {} {} fftfilt (@var{b}, @var{x}, @var{n}) ## Filter @var{x} with the FIR filter @var{b} using the FFT. ## ## If @var{x} is a matrix, filter each column of the matrix. ## ## Given the optional third argument, @var{n}, @code{fftfilt} uses the ## overlap-add method to filter @var{x} with @var{b} using an N-point FFT@. ## The FFT size must be an even power of 2 and must be greater than or equal to ## the length of @var{b}. If the specified @var{n} does not meet these ## criteria, it is automatically adjusted to the nearest value that does. ## ## @seealso{filter, filter2} ## @end deftypefn function y = fftfilt (b, x, n) ## If N is not specified explicitly, we do not use the overlap-add ## method at all because loops are really slow. Otherwise, we only ## ensure that the number of points in the FFT is the smallest power ## of two larger than N and length(b). This could result in length ## one blocks, but if the user knows better ... if (nargin < 2) print_usage (); endif transpose = (rows (x) == 1); if (transpose) x = x.'; endif [r_x, c_x] = size (x); [r_b, c_b] = size (b); if (! isvector (b)) error ("fftfilt: B must be a vector"); endif if (ndims (x) != 2) error ("fftfilt: X must be a 1-D or 2-D array"); endif l_b = r_b * c_b; b = reshape (b, l_b, 1); if (nargin == 2) ## Use FFT with the smallest power of 2 which is >= length (x) + ## length (b) - 1 as number of points ... n = 2 ^ nextpow2 (r_x + l_b - 1); B = fft (b, n); y = ifft (fft (x, n) .* B(:, ones (1, c_x))); else ## Use overlap-add method ... if (! (isscalar (n))) error ("fftfilt: N has to be a scalar"); endif n = 2 ^ nextpow2 (max ([n, l_b])); L = n - l_b + 1; B = fft (b, n); B = B(:, ones (c_x,1)); R = ceil (r_x / L); y = zeros (r_x, c_x); for r = 1:R lo = (r - 1) * L + 1; hi = min (r * L, r_x); tmp = zeros (n, c_x); tmp(1:(hi-lo+1),:) = x(lo:hi,:); tmp = ifft (fft (tmp) .* B); hi = min (lo+n-1, r_x); y(lo:hi,:) = y(lo:hi,:) + tmp(1:(hi-lo+1),:); endfor endif y = y(1:r_x, :); ## Final cleanups: ## - If both b and x are real, y should be real. ## - If b is real and x is imaginary, y should be imaginary. ## - If b is imaginary and x is real, y should be imaginary. ## - If both b and x are imaginary, y should be real. xisreal = all (imag (x) == 0); xisimag = all (real (x) == 0); if (all (imag (b) == 0)) y (:,xisreal) = real (y (:,xisreal)); y (:,xisimag) = complex (real (y (:,xisimag)) * 0, imag (y (:,xisimag))); elseif (all (real (b) == 0)) y (:,xisreal) = complex (real (y (:,xisreal)) * 0, imag (y (:,xisreal))); y (:,xisimag) = real (y (:,xisimag)); endif ## - If both x and b are integer in both real and imaginary ## components, y should be integer. if (! any (b - fix (b))) idx = find (! any (x - fix (x))); y (:, idx) = round (y (:, idx)); endif ## Transpose after cleanup, otherwise rounding fails. if (transpose) y = y.'; endif endfunction %!shared b, x, r %!testif HAVE_FFTW %! b = [1 1]; %! x = [1, zeros(1,9)]; %! assert (fftfilt (b, x ), [1 1 0 0 0 0 0 0 0 0] ); %! assert (fftfilt (b, x.'), [1 1 0 0 0 0 0 0 0 0].'); %! assert (fftfilt (b.',x ), [1 1 0 0 0 0 0 0 0 0] ); %! assert (fftfilt (b.',x.'), [1 1 0 0 0 0 0 0 0 0].'); %! assert (fftfilt (b, [x.' x.']), [1 1 0 0 0 0 0 0 0 0].'*[1 1]); %! assert (fftfilt (b, [x.'+2*eps x.']) == [1 1 0 0 0 0 0 0 0 0].'*[1 1], [false(10, 1) true(10, 1)]); %!testif HAVE_FFTW %! r = sqrt (1/2) * (1+i); %! b = b*r; %! assert (fftfilt (b, x ), r*[1 1 0 0 0 0 0 0 0 0] , eps ); %! assert (fftfilt (b, r*x), r*r*[1 1 0 0 0 0 0 0 0 0], 2*eps); %! assert (fftfilt (b, x.'), r*[1 1 0 0 0 0 0 0 0 0].', eps ); %!testif HAVE_FFTW %! b = [1 1]; %! x = zeros (10,3); x(1,1)=-1; x(1,2)=1; %! y0 = zeros (10,3); y0(1:2,1)=-1; y0(1:2,2)=1; %! y = fftfilt (b, x); %! assert (y0, y); %! y = fftfilt (b*i, x); %! assert (y0*i, y); %! y = fftfilt (b, x*i); %! assert (y0*i, y); %! y = fftfilt (b*i, x*i); %! assert (-y0, y); %! x = rand (10, 1); %! y = fftfilt (b, [x x*i]); %! assert (true, isreal (y(:,1))); %! assert (false, any (real (y(:,2)))); %!testif HAVE_FFTW %! b = rand (10, 1); %! x = rand (10, 1); %! y0 = filter (b, 1, x); %! y = fftfilt (b, x); %! assert (y0, y, 16*eps); %! y0 = filter (b*i, 1, x*i); %! y = fftfilt (b*i, x*i); %! assert (y0, y, 16*eps); %!testif HAVE_FFTW %! b = rand (10, 1) + i*rand (10, 1); %! x = rand (10, 1) + i*rand (10, 1); %! y0 = filter (b, 1, x); %! y = fftfilt (b, x); %! assert (y0, y, 55*eps); ## Test input validation %!error fftfilt (1) %!error fftfilt (1, 2, 3, 4) %!error fftfilt (ones (2), 1) %!error fftfilt (2, ones (3,3,3)) %!error fftfilt (2, 1, ones (2))