NEWS

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gsignal 0.3.7

• date: 240909
• Fixed issue #21: findpeaks() crashes on call to pracma::polyfit
• Fixed test on freqz which resulted in precision error on CRAN

gsignal 0.3.6

• date: 20240827
• Fixed issue #9: differences between freqz() and signal.scipy.freqz
  • updated freqz() to match current Octave version
  • implemented proper freqz.Sos() instead of converting to Arma
  • freqz.Zpg() converts to Sos instead of Arma
• Implemented changes in 'Octave' 'signal' 1.4.5 with respect to 1.4.1
  • added tests for cplxreal() (gsignal did not have Octave bug #60606)
  • added test for cheb2ap() (gsignal did not have Octave bug #58218)
  • all other changes concerned code style or documentation
• correct typos in stft.R (H. Dieter Wilhelm - pull request #10)
• Negate the signal reversed in time at both ends in filtfilt() (Rafael Laboissière - pull request #12)
• add check on NULL value in zapIm()
• Fixed issue #15 (loeriver): incorrect results and error in residuez()
  • removed Cong() on calculation of k
  • made calculation of r and p conditional
• Changed coefficients of the hamming() window function as in Matlab/Octave
• Fixed issue #17 (dipterix): decimate() not compatible with Matlab
  • replaced call to fftfilt() with filtfilt() if FIR filter is requested
• Bugfix in fir1(): adapted calculation of w_o
• Fixed issue #19 (jefferis): changed control flow logic in findpeaks() (line 174)
• Adapt freqs() to match freqz() - delete freqs_plot.R and add function freqs_plot() to freqs.R.

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gsignal 0.3-5 (2022-05-15)

• date: 20220514
• Fixed Discussion #6: remove padding to nearest power of 2 in pwelch()
• Fixed Github Issue #5: returning matrix when input is matrix in pwelch()
• Adapted e-mail addresses in mexihat, morlet, nutallwin, pburg, pyulear
• use inherits() instead of direct comparison of class name in ar_psd, findpeaks, pwelch, sgolayfilt, upfirdn
• defined plot methods for ar_psd, pwelch, specgram classes
• Fixed Github Issue #7: decimate with a matrix;, added "fir" argument to ftype

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gsignal 0.3-4 (2022-04-05)

• date: 20220404
• Fixed test failure in tests/testthat/test_miscellaneous_Functions.R

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gsignal 0.3-3 (2022-03-30)

• date: 20220330
• Fixed Github Issue #3: Problems with fftfilt() when FFT length is provided by user
• copy attributes of input object x to output in functions filter, filtfilt, sosfilt, fftfilt
• copy dimnames of input object x to output in functions upfirdn, resample, upsample, upsamplefill, downsample, decimate, detrend, fht, sgolayfilt
• added ultrwin() function
• adapted filter() to allow data and filter coefficients to be of type complex
• adapted sosfilt() to allow data and filter coefficients to be of type complex
• bugfix in pwelch() for multivariate input
• Fixed Github Issue #4: Problem with hilbert() for small amplitude signals
• added isConjSymm() function to gsignal-internal
• adapted ifft() to use isConjSymm() instead of ZapIm()
• reduced default tolerance for isWhole() and zapIm()
• bugfix in detrend(): function now returns a vector if input was a vector
• bugfix in filtfilt(): corrected bug in computing filter ends (default and Sos methods)

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gsignal 0.3-2 (2021-05-18)

• date: 20210518
• corrected CRAN WARNINGs on ATLAS, MKL, valgrind, fedora, solaris
• corrected import NOTE for grDevices
• adapted code in vignette "gsignal"
• use explicit tolerance in testthat tests
• added badges and logo (just for the fun of it)
• sort zeros and poles on output in sos2zp(), tf2zp()
• use matrix() instead of as.matrix() in functions dct(), idct(), czt(), dst(), idst(), fht(), ifht()
• minor bugfix in arburg()
• bugfix in filter.cpp: resize a and b vectors, length of zi
• adapted some examples

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gsignal 0.3-1 (2021-05-03)

• date: 20210502
• added 'signals' data frame
• cleaned code
• minor bugfixes
• updated tests
• added vignette

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gsignal 0.3-0

• date: 20210411
• Bugfixes in pwelch(), butter(), as.Arma.Sos(), as.Sos.Zpg(), sos2tf()
• Added 'output' parameter to butter(), cheby1(), cheby2(), ellip()
• Redesigned filter() to correct problems with initial conditions (now direct-form II)
• Return objects of respective class tf2zp(), tf2sos(), zp2sos(), zp2tf(), sos2tf(), sos2zp()
• Added 'order' argument to zp2sos(); changed default ordering
• Added filter_zi() function
• Redesigned sosfilt(); added support for initial conditions
• Adapted filtfilt(): use padding and Gustafsson method for initial conditions
• Function sgolayfilt(): if input x is a matrix, filter its columns
• Replace 'dim' argument by 'MARGIN' in functions cplxpair(), cplxpair(), medfilt1()
• Solved numerical precision error in chebwin() and cheb() functions
• Bugfix in cplxpair(); added additional tests
• Return vector if input is a vector in function czt()
• Added range parameter ('half' or 'whole') in function pwelch()
• Bugfix in calculating time points, function stft()
• Changed plotting to S3 functions in function specgram()

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gsignal 0.2-0

• date: 20201218
• completed documentation
• adapted examples and links
• license changed to GPL-3 in accordance with Octave signal package license

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gsignal 0.1-0

• date: 20201213

• initial setup. Functions:

• Signals: buffer, chirp, cmorwavf, diric, gauspuls, gmonopuls, mexihat, meyeraux, morlet, pulstran, rectpuls, sawtooth, shanwavf, shiftdata, sigmoid_train, sinetone, sinewave, specgram, square, tripuls, udecode, uencode, unshiftdata

• Signal Measurement: findpeaks, peak2peak, peak2rms, rms, rssq

• Correlation and Convolution: cconv, convmtx, wconv, xcorr, xcorr2, xcov

• Filtering: fftfilt, filter, filter2, filtfilt, filtic, medfilt1, movingrms, sgolayfilt, sosfilt

• Filter Analysis: freqs, freqs_plot, freqz, freqz_plot, fwhm, grpdelay, impz, zplane

• Filter Conversion: polystab, residued, residuez, sos2tf, sos2zp, tf2sos, tf2zp, zp2sos, zp2tf

• IIR Filter Design: besselap, besself, bilinear, buttap, butter, buttord, cheb, cheb1ap, cheb1ord, cheb2ap, cheb2ord, cheby1, cheby2 ellip, ellipap, ellipord, iirlp2mb, impinvar, invimpinvar, ncauer, pei_tseng_notch, sftrans

• FIR Filter Design: cl2bp, fir1, fir2, firls, kaiserord, qp_kaiser, remez, sgolay

• Transforms: bitrevorder, cceps, cplxreal, czt, dct, dct2, dctmtx, dftmtx, digitrevorder, dst, dwt, fftshift, fht, fwht, hilbert, idct, idct2, idst, ifft, ifftshift, ifht, ifwht, imvfft, rceps, stft

• Power Spectrum Analysis: ar_psd, cohere, cpsd, csd, db2pow, mscohere, pburg, pow2db, pwelch, pyulear, tfe, tfestimate

• Window Functions: barthannwin, bartlett, blackman, blackmanharris, blackmannuttall, bohmanwin, boxcar, chebwin, flattopwin, gaussian, gausswin, hamming, hanning, hann, kaiser, nuttallwin, parzenwin, rectwin, triang, tukeywin, ultrwin, welchwin

• System Identification: arburg, aryule, invfreq, invfreqs, invfreqz, levinson

• Sample Rate Change: decimate, downsample, interp, resample, upfirdn, upsample

• Utility: clustersegment, fracshift, marcumq, primitive, sampled2continuous, schtrig, upsamplefill, wkeep, zerocrossing

• Standard Functions: detrend, pad, postpad, prepad

• Miscellaneous: Arma, Ma, Zpg, Sos, FilterSpecs, fftconv, unwrap, cplxpair, poly, conv, conv2, residue, polyreduce, mpoles