コード例 #1
0
def test_iirfilter():
    # dataset with one feature from two waves
    t = np.linspace(0, 1.0, 2001)
    xlow = np.sin(2 * np.pi * 5 * t)
    xhigh = np.sin(2 * np.pi * 250 * t)
    x = xlow + xhigh
    ds = Dataset(x, sa={'sid': np.arange(len(x))}, fa={'fid':['theone']})

    # butterworth filter with a cutoff between the waves
    from scipy import signal
    b, a = signal.butter(8, 0.125)
    mds = iir_filter(ds, b, a, padlen=150)
    # check we get just the slow wave out (compensate for edge artifacts)
    assert_false(np.sum(np.abs(mds.samples[100:-100,0] - xlow[100:-100]) > 0.001))
    assert_equal(len(ds.sa), len(mds.sa))
    assert_equal(len(ds.fa), len(mds.fa))
    assert_array_equal(ds.fa.fid, mds.fa.fid)
    assert_array_equal(ds.sa.sid, mds.sa.sid)
コード例 #2
0
ファイル: test_filters.py プロジェクト: Anhmike/PyMVPA
def test_iirfilter():
    # dataset with one feature from two waves
    t = np.linspace(0, 1.0, 2001)
    xlow = np.sin(2 * np.pi * 5 * t)
    xhigh = np.sin(2 * np.pi * 250 * t)
    x = xlow + xhigh
    ds = Dataset(x, sa={'sid': np.arange(len(x))}, fa={'fid':['theone']})

    # butterworth filter with a cutoff between the waves
    from scipy import signal
    b, a = signal.butter(8, 0.125)
    mds = iir_filter(ds, b, a, padlen=150)
    # check we get just the slow wave out (compensate for edge artifacts)
    assert_false(np.sum(np.abs(mds.samples[100:-100,0] - xlow[100:-100]) > 0.001))
    assert_equal(len(ds.sa), len(mds.sa))
    assert_equal(len(ds.fa), len(mds.fa))
    assert_array_equal(ds.fa.fid, mds.fa.fid)
    assert_array_equal(ds.sa.sid, mds.sa.sid)
コード例 #3
0
ファイル: cmd_preproc.py プロジェクト: neurosbh/PyMVPA
def run(args):
    if not args.chunks is None:
        # apply global "chunks" setting
        for cattr in ('detrend_chunks', 'zscore_chunks'):
            if getattr(args, cattr) is None:
                # only overwrite if individual option is not given
                args.__setattr__(cattr, args.chunks)
    ds = arg2ds(args.data)
    if not args.poly_detrend is None:
        if not args.detrend_chunks is None \
           and not args.detrend_chunks in ds.sa:
            raise ValueError(
                "--detrend-chunks attribute '%s' not found in dataset" %
                args.detrend_chunks)
        from mvpa2.mappers.detrend import poly_detrend
        verbose(1, "Detrend")
        poly_detrend(ds,
                     polyord=args.poly_detrend,
                     chunks_attr=args.detrend_chunks,
                     opt_regs=args.detrend_regrs,
                     space=args.detrend_coords)
    if args.filter_passband is not None:
        from mvpa2.mappers.filters import iir_filter
        from scipy.signal import butter, buttord
        if args.sampling_rate is None or args.filter_stopband is None:
            raise ValueError("spectral filtering requires specification of "
                             "--filter-stopband and --sampling-rate")
        # determine filter type
        nyquist = args.sampling_rate / 2.0
        if len(args.filter_passband) > 1:
            btype = 'bandpass'
            if not len(args.filter_passband) == len(args.filter_stopband):
                raise ValueError(
                    "passband and stopband specifications have to "
                    "match in size")
            wp = [v / nyquist for v in args.filter_passband]
            ws = [v / nyquist for v in args.filter_stopband]
        elif args.filter_passband[0] < args.filter_stopband[0]:
            btype = 'lowpass'
            wp = args.filter_passband[0] / nyquist
            ws = args.filter_stopband[0] / nyquist
        elif args.filter_passband[0] > args.filter_stopband[0]:
            btype = 'highpass'
            wp = args.filter_passband[0] / nyquist
            ws = args.filter_stopband[0] / nyquist
        else:
            raise ValueError("invalid specification of Butterworth filter")
        # create filter
        verbose(1, "Spectral filtering (%s)" % (btype, ))
        try:
            ord, wn = buttord(wp,
                              ws,
                              args.filter_passloss,
                              args.filter_stopattenuation,
                              analog=False)
            b, a = butter(ord, wn, btype=btype)
        except OverflowError:
            raise ValueError(
                "cannot contruct Butterworth filter for the given "
                "specification")
        ds = iir_filter(ds, b, a)

    if args.zscore:
        from mvpa2.mappers.zscore import zscore
        verbose(1, "Z-score")
        zscore(ds, chunks_attr=args.zscore_chunks, params=args.zscore_params)
        verbose(3, "Dataset summary %s" % (ds.summary()))
    # invariants?
    if not args.strip_invariant_features is None:
        from mvpa2.datasets.miscfx import remove_invariant_features
        ds = remove_invariant_features(ds)
    # and store
    ds2hdf5(ds, args.output, compression=args.hdf5_compression)
    return ds
コード例 #4
0
ファイル: cmd_preproc.py プロジェクト: robbisg/PyMVPA
def run(args):
    if args.chunks is not None:
        # apply global "chunks" setting
        for cattr in ("detrend_chunks", "zscore_chunks"):
            if getattr(args, cattr) is None:
                # only overwrite if individual option is not given
                args.__setattr__(cattr, args.chunks)
    ds = arg2ds(args.data)
    if args.poly_detrend is not None:
        if args.detrend_chunks is not None and not args.detrend_chunks in ds.sa:
            raise ValueError("--detrend-chunks attribute '%s' not found in dataset" % args.detrend_chunks)
        from mvpa2.mappers.detrend import poly_detrend

        verbose(1, "Detrend")
        poly_detrend(
            ds,
            polyord=args.poly_detrend,
            chunks_attr=args.detrend_chunks,
            opt_regs=args.detrend_regrs,
            space=args.detrend_coords,
        )
    if args.filter_passband is not None:
        from mvpa2.mappers.filters import iir_filter
        from scipy.signal import butter, buttord

        if args.sampling_rate is None or args.filter_stopband is None:
            raise ValueError("spectral filtering requires specification of " "--filter-stopband and --sampling-rate")
        # determine filter type
        nyquist = args.sampling_rate / 2.0
        if len(args.filter_passband) > 1:
            btype = "bandpass"
            if not len(args.filter_passband) == len(args.filter_stopband):
                raise ValueError("passband and stopband specifications have to " "match in size")
            wp = [v / nyquist for v in args.filter_passband]
            ws = [v / nyquist for v in args.filter_stopband]
        elif args.filter_passband[0] < args.filter_stopband[0]:
            btype = "lowpass"
            wp = args.filter_passband[0] / nyquist
            ws = args.filter_stopband[0] / nyquist
        elif args.filter_passband[0] > args.filter_stopband[0]:
            btype = "highpass"
            wp = args.filter_passband[0] / nyquist
            ws = args.filter_stopband[0] / nyquist
        else:
            raise ValueError("invalid specification of Butterworth filter")
        # create filter
        verbose(1, "Spectral filtering (%s)" % (btype,))
        try:
            ord, wn = buttord(wp, ws, args.filter_passloss, args.filter_stopattenuation, analog=False)
            b, a = butter(ord, wn, btype=btype)
        except OverflowError:
            raise ValueError("cannot contruct Butterworth filter for the given " "specification")
        ds = iir_filter(ds, b, a)

    if args.zscore:
        from mvpa2.mappers.zscore import zscore

        verbose(1, "Z-score")
        zscore(ds, chunks_attr=args.zscore_chunks, params=args.zscore_params)
        verbose(3, "Dataset summary %s" % (ds.summary()))
    # invariants?
    if args.strip_invariant_features is not None:
        from mvpa2.datasets.miscfx import remove_invariant_features

        ds = remove_invariant_features(ds)
    # and store
    ds2hdf5(ds, args.output, compression=args.hdf5_compression)
    return ds