Array API Standard Support: signal#

This page explains some caveats of the signal module and provides (currently incomplete) tables about the CPU, GPU and JIT support.

Caveats#

JAX and CuPy provide alternative implementations for some signal functions. When such a function is called, a decorator decides which implementation to use by inspecting the xp parameter.

Hence, there can be, especially during CI testing, discrepancies in behavior between the default NumPy-based implementation and the JAX and CuPy backends. Skipping the incompatible backends in unit tests, as described in the Adding tests section, is the currently recommended workaround.

The functions are decorated by the code in file scipy/signal/_support_alternative_backends.py:

  1import functools
  2import types
  3from scipy._lib._array_api import (
  4    is_cupy, is_jax, scipy_namespace_for, SCIPY_ARRAY_API, xp_capabilities
  5)
  6
  7from ._signal_api import *   # noqa: F403
  8from . import _signal_api
  9from . import _delegators
 10__all__ = _signal_api.__all__
 11
 12
 13MODULE_NAME = 'signal'
 14
 15# jax.scipy.signal has only partial coverage of scipy.signal, so we keep the list
 16# of functions we can delegate to JAX
 17# https://jax.readthedocs.io/en/latest/jax.scipy.html
 18JAX_SIGNAL_FUNCS = [
 19    'fftconvolve', 'convolve', 'convolve2d', 'correlate', 'correlate2d',
 20    'csd', 'detrend', 'istft', 'welch'
 21]
 22
 23# some cupyx.scipy.signal functions are incompatible with their scipy counterparts
 24CUPY_BLACKLIST = [
 25    'abcd_normalize', 'bessel', 'besselap', 'envelope', 'get_window', 'lfilter_zi',
 26    'sosfilt_zi', 'remez',
 27]
 28
 29# freqz_sos is a sosfreqz rename, and cupy does not have the new name yet (in v13.x)
 30CUPY_RENAMES = {'freqz_sos': 'sosfreqz'}
 31
 32
 33def delegate_xp(delegator, module_name):
 34    def inner(func):
 35        @functools.wraps(func)
 36        def wrapper(*args, **kwds):
 37            try:
 38                xp = delegator(*args, **kwds)
 39            except TypeError:
 40                # object arrays
 41                if func.__name__ == "tf2ss":
 42                    import numpy as np
 43                    xp = np
 44                else:
 45                    raise
 46
 47            # try delegating to a cupyx/jax namesake
 48            if is_cupy(xp) and func.__name__ not in CUPY_BLACKLIST:
 49                func_name = CUPY_RENAMES.get(func.__name__, func.__name__)
 50
 51                # https://github.com/cupy/cupy/issues/8336
 52                import importlib
 53                cupyx_module = importlib.import_module(f"cupyx.scipy.{module_name}")
 54                cupyx_func = getattr(cupyx_module, func_name)
 55                kwds.pop('xp', None)
 56                return cupyx_func(*args, **kwds)
 57            elif is_jax(xp) and func.__name__ in JAX_SIGNAL_FUNCS:
 58                spx = scipy_namespace_for(xp)
 59                jax_module = getattr(spx, module_name)
 60                jax_func = getattr(jax_module, func.__name__)
 61                kwds.pop('xp', None)
 62                return jax_func(*args, **kwds)
 63            else:
 64                # the original function
 65                return func(*args, **kwds)
 66        return wrapper
 67    return inner
 68
 69
 70# Although most of these functions currently exist in CuPy and some in JAX,
 71# there are no alternative backend tests for any of them in the current
 72# test suite. Each will be documented as np_only until tests are added.
 73untested = {
 74    "argrelextrema",
 75    "argrelmax",
 76    "argrelmin",
 77    "band_stop_obj",
 78    "bode",
 79    "check_NOLA",
 80    "chirp",
 81    "coherence",
 82    "csd",
 83    "czt",
 84    "czt_points",
 85    "dbode",
 86    "dfreqresp",
 87    "dlsim",
 88    "dstep",
 89    "find_peaks",
 90    "find_peaks_cwt",
 91    "freqresp",
 92    "gausspulse",
 93    "iirdesign", # There's no reason this shouldn't work. It just needs tests.
 94    "istft",
 95    "lombscargle",
 96    "lsim",
 97    "max_len_seq",
 98    "peak_prominences",
 99    "peak_widths",
100    "periodogram",
101    "place_poles",
102    "sepfir2d",
103    "ss2tf",
104    "ss2zpk",
105    "step",
106    "sweep_poly",
107    "symiirorder1",
108    "symiirorder2",
109    "tf2ss",
110    "unit_impulse",
111    "zoom_fft",
112    "zpk2ss",
113}
114
115
116def get_default_capabilities(func_name, delegator):
117    if delegator is None or func_name in untested:
118        return xp_capabilities(np_only=True)
119    return xp_capabilities()
120
121bilinear_extra_note = \
122    """CuPy does not accept complex inputs.
123
124    """
125
126uses_choose_conv_extra_note = \
127    """CuPy does not support inputs with ``ndim>1`` when ``method="auto"``
128    but does support higher dimensional arrays for ``method="direct"``
129    and ``method="fft"``.
130
131    """
132
133resample_poly_extra_note = \
134    """CuPy only supports ``padtype="constant"``.
135
136    """
137
138upfirdn_extra_note = \
139    """CuPy only supports ``mode="constant"`` and ``cval=0.0``.
140
141    """
142
143xord_extra_note = \
144    """The ``torch`` backend on GPU does not support the case where
145    `wp` and `ws` specify a Bandstop filter.
146
147    """
148
149convolve2d_extra_note = \
150    """The JAX backend only supports ``boundary="fill"`` and ``fillvalue=0``.
151
152    """
153
154zpk2tf_extra_note = \
155    """The CuPy and JAX backends both support only 1d input.
156
157    """
158
159abcd_normalize_extra_note = \
160    """The result dtype when all array inputs are of integer dtype is the
161    backend's current default floating point dtype.
162
163    """
164
165welch_extra_note = \
166    """Support for CuPy and JAX is provided by delegation to
167    ``cupyx.scipy.signal.welch`` and ``jax.scipy.signal.welch``.
168
169    For single-precision input (``float32`` or ``complex64``), JAX returns the sample
170    frequencies in ``float32``, whereas SciPy and CuPy always return them in
171    ``float64``.
172    """
173
174capabilities_overrides = {
175    "abcd_normalize": xp_capabilities(extra_note=abcd_normalize_extra_note),
176    "bessel": xp_capabilities(cpu_only=True, jax_jit=False, allow_dask_compute=True),
177    "bilinear": xp_capabilities(cpu_only=True, exceptions=["cupy"],
178                                jax_jit=False, allow_dask_compute=True,
179                                reason="Uses np.polynomial.Polynomial",
180                                extra_note=bilinear_extra_note),
181    "bilinear_zpk": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
182                                    jax_jit=False, allow_dask_compute=True),
183    "butter": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
184                              allow_dask_compute=True),
185    "buttord": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
186                               jax_jit=False, allow_dask_compute=True,
187                               extra_note=xord_extra_note),
188    "cheb1ord": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
189                                jax_jit=False, allow_dask_compute=True,
190                                extra_note=xord_extra_note),
191    "cheb2ord": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
192                                jax_jit=False, allow_dask_compute=True,
193                                extra_note=xord_extra_note),
194    "cheby1": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
195                              allow_dask_compute=True),
196
197    "cheby2": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
198                              allow_dask_compute=True),
199    "cont2discrete": xp_capabilities(np_only=True, exceptions=["cupy"]),
200    "convolve": xp_capabilities(cpu_only=True, exceptions=["cupy", "jax.numpy"],
201                                allow_dask_compute=True,
202                                extra_note=uses_choose_conv_extra_note),
203    "convolve2d": xp_capabilities(cpu_only=True, exceptions=["cupy", "jax.numpy"],
204                                  allow_dask_compute=True,
205                                  extra_note=convolve2d_extra_note),
206    "correlate": xp_capabilities(cpu_only=True, exceptions=["cupy", "jax.numpy"],
207                                 allow_dask_compute=True,
208                                 extra_note=uses_choose_conv_extra_note),
209    "correlate2d": xp_capabilities(cpu_only=True, exceptions=["cupy", "jax.numpy"],
210                                   allow_dask_compute=True,
211                                   extra_note=convolve2d_extra_note),
212    "correlation_lags": xp_capabilities(out_of_scope=True),
213    "cspline1d": xp_capabilities(cpu_only=True, exceptions=["cupy"],
214                                 jax_jit=False, allow_dask_compute=True),
215    "cspline1d_eval": xp_capabilities(cpu_only=True, exceptions=["cupy"],
216                                      jax_jit=False, allow_dask_compute=True),
217    "cspline2d": xp_capabilities(cpu_only=True, exceptions=["cupy"],
218                                 jax_jit=False, allow_dask_compute=True),
219    "deconvolve": xp_capabilities(cpu_only=True, exceptions=["cupy"],
220                                  jax_jit=False, allow_dask_compute=True),
221    "decimate": xp_capabilities(np_only=True, exceptions=["cupy"]),
222    "detrend": xp_capabilities(cpu_only=True, exceptions=["cupy", "jax.numpy"],
223                               allow_dask_compute=True),
224    "dimpulse": xp_capabilities(np_only=True, exceptions=["cupy"]),
225    "dlti": xp_capabilities(np_only=True,
226                            reason="works in CuPy but delegation isn't set up yet"),
227    "ellip": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
228                             allow_dask_compute=True,
229                             reason="scipy.special.ellipk"),
230    "ellipord": xp_capabilities(cpu_only=True, exceptions=["cupy"],
231                                jax_jit=False, allow_dask_compute=True,
232                                reason="scipy.special.ellipk"),
233    "filtfilt": xp_capabilities(cpu_only=True, exceptions=["cupy"],
234                                allow_dask_compute=True, jax_jit=False),
235    "findfreqs": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
236                                 jax_jit=False, allow_dask_compute=True),
237    "firls": xp_capabilities(cpu_only=True, allow_dask_compute=True, jax_jit=False,
238                             reason="lstsq"),
239    "firwin": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
240                              jax_jit=False, allow_dask_compute=True),
241    "firwin2": xp_capabilities(cpu_only=True, exceptions=["cupy"],
242                               jax_jit=False, allow_dask_compute=True,
243                               reason="firwin2 uses np.interp"),
244    "freqs": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
245                             jax_jit=False, allow_dask_compute=True),
246    "freqs_zpk": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
247                                 jax_jit=False, allow_dask_compute=True),
248    "freqz": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
249                             jax_jit=False, allow_dask_compute=True),
250    "freqz_sos": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
251                                 jax_jit=False, allow_dask_compute=True),
252    "group_delay": xp_capabilities(cpu_only=True, exceptions=["cupy"],
253                                   jax_jit=False, allow_dask_compute=True),
254    "invres": xp_capabilities(np_only=True, exceptions=["cupy"]),
255    "invresz": xp_capabilities(np_only=True, exceptions=["cupy"]),
256    "iircomb": xp_capabilities(xfail_backends=[("jax.numpy", "inaccurate")]),
257    "iirfilter": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
258                                 jax_jit=False, allow_dask_compute=True),
259    "kaiser_atten": xp_capabilities(
260        out_of_scope=True, reason="scalars in, scalars out"
261    ),
262    "kaiser_beta": xp_capabilities(out_of_scope=True, reason="scalars in, scalars out"),
263    "kaiserord": xp_capabilities(out_of_scope=True, reason="scalars in, scalars out"),
264    "lfilter": xp_capabilities(cpu_only=True, exceptions=["cupy"],
265                               allow_dask_compute=True, jax_jit=False),
266    "lfilter_zi": xp_capabilities(cpu_only=True, allow_dask_compute=True,
267                                  jax_jit=False),
268    "lfiltic": xp_capabilities(cpu_only=True, exceptions=["cupy"],
269                               allow_dask_compute=True, jax_jit=False),
270    "lp2bp": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
271                             allow_dask_compute=True, jax_jit=False),
272    "lp2bp_zpk": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
273                                 allow_dask_compute=True, jax_jit=False),
274    "lp2bs": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
275                             allow_dask_compute=True, jax_jit=False),
276    "lp2bs_zpk": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
277                                 allow_dask_compute=True, jax_jit=False),
278    "lp2lp": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
279                             allow_dask_compute=True, jax_jit=False),
280    "lp2lp_zpk": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
281                                 allow_dask_compute=True, jax_jit=False),
282    "lp2hp": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
283                             allow_dask_compute=True, jax_jit=False),
284    "lp2hp_zpk": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
285                                 allow_dask_compute=True, jax_jit=False),
286    "lti": xp_capabilities(np_only=True,
287                            reason="works in CuPy but delegation isn't set up yet"),
288    "medfilt": xp_capabilities(cpu_only=True, exceptions=["cupy"],
289                               allow_dask_compute=True, jax_jit=False,
290                               reason="uses scipy.ndimage.rank_filter"),
291    "medfilt2d": xp_capabilities(cpu_only=True, exceptions=["cupy"],
292                                 allow_dask_compute=True, jax_jit=False,
293                                 reason="c extension module"),
294    "minimum_phase": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
295                                     allow_dask_compute=True, jax_jit=False),
296    "normalize": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
297                                 jax_jit=False, allow_dask_compute=True),
298    "oaconvolve": xp_capabilities(
299        cpu_only=True, exceptions=["cupy", "torch"],
300        xfail_backends=[("dask.array", "wrong answer")],
301    ),
302    "order_filter": xp_capabilities(cpu_only=True, exceptions=["cupy"],
303                                    allow_dask_compute=True, jax_jit=False,
304                                    reason="uses scipy.ndimage.rank_filter"),
305    "qspline1d": xp_capabilities(cpu_only=True, exceptions=["cupy"],
306                                 jax_jit=False, allow_dask_compute=True),
307    "qspline1d_eval": xp_capabilities(cpu_only=True, exceptions=["cupy"],
308                                      jax_jit=False, allow_dask_compute=True),
309    "qspline2d": xp_capabilities(np_only=True, exceptions=["cupy"]),
310    "remez": xp_capabilities(cpu_only=True, allow_dask_compute=True, jax_jit=False),
311    "resample_poly": xp_capabilities(
312        cpu_only=True, exceptions=["cupy"],
313        jax_jit=False, skip_backends=[("dask.array", "XXX something in dask")],
314        extra_note=resample_poly_extra_note,
315    ),
316    "residue": xp_capabilities(np_only=True, exceptions=["cupy"]),
317    "residuez": xp_capabilities(np_only=True, exceptions=["cupy"]),
318    "savgol_filter": xp_capabilities(cpu_only=True, exceptions=["cupy"],
319                                     jax_jit=False,
320                                     reason="convolve1d is cpu-only"),
321    "sawtooth": xp_capabilities(jax_jit=False,
322                                skip_backends=[("dask.array", "dask tests fail")]),
323    "sos2zpk": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
324                               allow_dask_compute=True),
325    "sos2tf": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
326                              allow_dask_compute=True),
327    "sosfilt": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
328                               allow_dask_compute=True),
329    "sosfilt_zi": xp_capabilities(cpu_only=True, allow_dask_compute=True,
330                                  jax_jit=False),
331    "sosfiltfilt": xp_capabilities(
332        cpu_only=True, exceptions=["cupy"], jax_jit=False,
333        skip_backends=[
334            (
335                "dask.array",
336                "sosfiltfilt directly sets shape attributes on arrays"
337                " which dask doesn't like"
338            ),
339            ("torch", "negative strides"),
340        ],
341    ),
342    "sosfreqz": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
343                                jax_jit=False, allow_dask_compute=True),
344    "spline_filter": xp_capabilities(cpu_only=True, exceptions=["cupy"],
345                                     jax_jit=False, allow_dask_compute=True),
346    "tf2sos": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
347                              allow_dask_compute=True),
348    "tf2zpk": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
349                              allow_dask_compute=True),
350    "unique_roots": xp_capabilities(np_only=True, exceptions=["cupy"]),
351    "upfirdn": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
352                               allow_dask_compute=True,
353                               reason="Cython implementation",
354                               extra_note=upfirdn_extra_note),
355    "vectorstrength": xp_capabilities(cpu_only=True, exceptions=["cupy", "torch"],
356                                      allow_dask_compute=True, jax_jit=False),
357    "welch": xp_capabilities(cpu_only=True, exceptions=["cupy", "jax.numpy"],
358                             allow_dask_compute=True,
359                             extra_note=welch_extra_note),
360    "wiener": xp_capabilities(cpu_only=True, exceptions=["cupy", "jax.numpy"],
361                              allow_dask_compute=True, jax_jit=False,
362                              reason="uses scipy.signal.correlate"),
363    "zpk2sos": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
364                               allow_dask_compute=True),
365    "zpk2tf": xp_capabilities(cpu_only=True, exceptions=["cupy"], jax_jit=False,
366                              allow_dask_compute=True,
367                              extra_note=zpk2tf_extra_note),
368    "spectrogram": xp_capabilities(out_of_scope=True),  # legacy
369    "stft": xp_capabilities(out_of_scope=True),  # legacy
370    "istft": xp_capabilities(out_of_scope=True),  # legacy
371    "check_COLA": xp_capabilities(out_of_scope=True),  # legacy
372}
373
374
375# ### decorate ###
376for obj_name in _signal_api.__all__:
377    bare_obj = getattr(_signal_api, obj_name)
378    delegator = getattr(_delegators, obj_name + "_signature", None)
379
380    if SCIPY_ARRAY_API and delegator is not None:
381        f = delegate_xp(delegator, MODULE_NAME)(bare_obj)
382    else:
383        f = bare_obj
384
385    if not isinstance(f, types.ModuleType):
386        capabilities = capabilities_overrides.get(
387            obj_name, get_default_capabilities(obj_name, delegator)
388        )
389        f = capabilities(f)  # pyrefly:ignore[not-callable]
390
391    # add the decorated function to the namespace, to be imported in __init__.py
392    vars()[obj_name] = f

Note that a function will only be decorated if the environment variable SCIPY_ARRAY_API is set and its signature is listed in the file scipy/signal/_delegators.py. E.g., for firwin, the signature function looks like this:

339def firwin_signature(numtaps, cutoff, *args, **kwds):
340    if isinstance(cutoff, int | float):
341        xp = np_compat
342    else:
343        xp = array_namespace(cutoff)
344    return xp

Support on CPU#

Legend

✔️ = supported

✖ = unsupported

N/A = out-of-scope

function/class

torch

jax

dask

CZT

ShortTimeFFT

StateSpace

TransferFunction

ZerosPolesGain

ZoomFFT

abcd_normalize

✔️

✔️

✔️

argrelextrema

argrelmax

argrelmin

band_stop_obj

bessel

✔️

✔️

✔️

besselap

✔️

✔️

✔️

bilinear

✔️

✔️

✔️

bilinear_zpk

✔️

✔️

✔️

bode

buttap

✔️

✔️

✔️

butter

✔️

✔️

✔️

buttord

✔️

✔️

✔️

cheb1ap

✔️

✔️

✔️

cheb1ord

✔️

✔️

✔️

cheb2ap

✔️

✔️

✔️

cheb2ord

✔️

✔️

✔️

cheby1

✔️

✔️

✔️

cheby2

✔️

✔️

✔️

check_COLA

N/A

N/A

N/A

check_NOLA

chirp

choose_conv_method

✔️

✔️

✔️

closest_STFT_dual_window

coherence

cont2discrete

convolve

✔️

✔️

✔️

convolve2d

✔️

✔️

✔️

correlate

✔️

✔️

✔️

correlate2d

✔️

✔️

✔️

correlation_lags

N/A

N/A

N/A

csd

cspline1d

✔️

✔️

✔️

cspline1d_eval

✔️

✔️

✔️

cspline2d

✔️

✔️

✔️

czt

czt_points

dbode

decimate

deconvolve

✔️

✔️

✔️

detrend

✔️

✔️

✔️

dfreqresp

dimpulse

dlsim

dlti

dstep

ellip

✔️

✔️

✔️

ellipap

✔️

✔️

✔️

ellipord

✔️

✔️

✔️

envelope

✔️

✔️

✔️

fftconvolve

✔️

✔️

✔️

filtfilt

✔️

✔️

✔️

find_peaks

find_peaks_cwt

findfreqs

✔️

✔️

✔️

firls

✔️

✔️

✔️

firwin

✔️

✔️

✔️

firwin2

✔️

✔️

✔️

firwin_2d

freqresp

freqs

✔️

✔️

✔️

freqs_zpk

✔️

✔️

✔️

freqz

✔️

✔️

✔️

freqz_sos

✔️

✔️

✔️

freqz_zpk

✔️

✔️

✔️

gammatone

✔️

✔️

✔️

gauss_spline

✔️

✔️

✔️

gausspulse

get_window

✔️

✔️

✔️

group_delay

✔️

✔️

✔️

hilbert

✔️

✔️

✔️

hilbert2

✔️

✔️

✔️

iircomb

✔️

✔️

iirdesign

iirfilter

✔️

✔️

✔️

iirnotch

✔️

✔️

✔️

iirpeak

✔️

✔️

✔️

impulse

✔️

✔️

✔️

invres

invresz

istft

N/A

N/A

N/A

kaiser_atten

N/A

N/A

N/A

kaiser_beta

N/A

N/A

N/A

kaiserord

N/A

N/A

N/A

lfilter

✔️

✔️

✔️

lfilter_zi

✔️

✔️

✔️

lfiltic

✔️

✔️

✔️

lombscargle

lp2bp

✔️

✔️

✔️

lp2bp_zpk

✔️

✔️

✔️

lp2bs

✔️

✔️

✔️

lp2bs_zpk

✔️

✔️

✔️

lp2hp

✔️

✔️

✔️

lp2hp_zpk

✔️

✔️

✔️

lp2lp

✔️

✔️

✔️

lp2lp_zpk

✔️

✔️

✔️

lsim

lti

max_len_seq

medfilt

✔️

✔️

✔️

medfilt2d

✔️

✔️

✔️

minimum_phase

✔️

✔️

✔️

normalize

✔️

✔️

✔️

oaconvolve

✔️

✔️

order_filter

✔️

✔️

✔️

peak_prominences

peak_widths

periodogram

place_poles

qspline1d

✔️

✔️

✔️

qspline1d_eval

✔️

✔️

✔️

qspline2d

remez

✔️

✔️

✔️

resample

✔️

✔️

✔️

resample_poly

✔️

✔️

residue

residuez

savgol_coeffs

✔️

✔️

✔️

savgol_filter

✔️

✔️

✔️

sawtooth

✔️

✔️

sepfir2d

sos2tf

✔️

✔️

✔️

sos2zpk

✔️

✔️

✔️

sosfilt

✔️

✔️

✔️

sosfilt_zi

✔️

✔️

✔️

sosfiltfilt

✔️

sosfreqz

✔️

✔️

✔️

spectrogram

N/A

N/A

N/A

spline_filter

✔️

✔️

✔️

square

✔️

✔️

✔️

ss2tf

ss2zpk

step

stft

N/A

N/A

N/A

sweep_poly

symiirorder1

symiirorder2

tf2sos

✔️

✔️

✔️

tf2ss

tf2zpk

✔️

✔️

✔️

unique_roots

unit_impulse

upfirdn

✔️

✔️

✔️

vectorstrength

✔️

✔️

✔️

welch

✔️

✔️

✔️

whittaker_henderson

wiener

✔️

✔️

✔️

zoom_fft

zpk2sos

✔️

✔️

✔️

zpk2ss

zpk2tf

✔️

✔️

✔️

Support on GPU#

Legend

✔️ = supported

✖ = unsupported

N/A = out-of-scope

function/class

cupy

torch

jax

CZT

ShortTimeFFT

StateSpace

TransferFunction

ZerosPolesGain

ZoomFFT

abcd_normalize

✔️

✔️

✔️

argrelextrema

argrelmax

argrelmin

band_stop_obj

bessel

besselap

✔️

✔️

✔️

bilinear

✔️

bilinear_zpk

✔️

✔️

bode

buttap

✔️

✔️

✔️

butter

✔️

buttord

✔️

✔️

cheb1ap

✔️

✔️

✔️

cheb1ord

✔️

✔️

cheb2ap

✔️

✔️

✔️

cheb2ord

✔️

✔️

cheby1

✔️

cheby2

✔️

check_COLA

N/A

N/A

N/A

check_NOLA

chirp

choose_conv_method

✔️

✔️

✔️

closest_STFT_dual_window

coherence

cont2discrete

✔️

convolve

✔️

✔️

convolve2d

✔️

✔️

correlate

✔️

✔️

correlate2d

✔️

✔️

correlation_lags

N/A

N/A

N/A

csd

cspline1d

✔️

cspline1d_eval

✔️

cspline2d

✔️

czt

czt_points

dbode

decimate

✔️

deconvolve

✔️

detrend

✔️

✔️

dfreqresp

dimpulse

✔️

dlsim

dlti

dstep

ellip

✔️

ellipap

✔️

✔️

✔️

ellipord

✔️

envelope

✔️

✔️

✔️

fftconvolve

✔️

✔️

✔️

filtfilt

✔️

find_peaks

find_peaks_cwt

findfreqs

✔️

✔️

firls

firwin

✔️

✔️

firwin2

✔️

firwin_2d

freqresp

freqs

✔️

✔️

freqs_zpk

✔️

✔️

freqz

✔️

✔️

freqz_sos

✔️

✔️

freqz_zpk

✔️

✔️

✔️

gammatone

✔️

✔️

✔️

gauss_spline

✔️

✔️

✔️

gausspulse

get_window

✔️

✔️

✔️

group_delay

✔️

hilbert

✔️

✔️

✔️

hilbert2

✔️

✔️

✔️

iircomb

✔️

✔️

iirdesign

iirfilter

✔️

✔️

iirnotch

✔️

✔️

✔️

iirpeak

✔️

✔️

✔️

impulse

✔️

✔️

✔️

invres

✔️

invresz

✔️

istft

N/A

N/A

N/A

kaiser_atten

N/A

N/A

N/A

kaiser_beta

N/A

N/A

N/A

kaiserord

N/A

N/A

N/A

lfilter

✔️

lfilter_zi

lfiltic

✔️

lombscargle

lp2bp

✔️

✔️

lp2bp_zpk

✔️

✔️

lp2bs

✔️

✔️

lp2bs_zpk

✔️

✔️

lp2hp

✔️

✔️

lp2hp_zpk

✔️

✔️

lp2lp

✔️

✔️

lp2lp_zpk

✔️

✔️

lsim

lti

max_len_seq

medfilt

✔️

medfilt2d

✔️

minimum_phase

✔️

✔️

normalize

✔️

✔️

oaconvolve

✔️

✔️

order_filter

✔️

peak_prominences

peak_widths

periodogram

place_poles

qspline1d

✔️

qspline1d_eval

✔️

qspline2d

✔️

remez

resample

✔️

✔️

✔️

resample_poly

✔️

residue

✔️

residuez

✔️

savgol_coeffs

✔️

✔️

✔️

savgol_filter

✔️

sawtooth

✔️

✔️

✔️

sepfir2d

sos2tf

✔️

sos2zpk

✔️

sosfilt

✔️

sosfilt_zi

sosfiltfilt

✔️

sosfreqz

✔️

✔️

spectrogram

N/A

N/A

N/A

spline_filter

✔️

square

✔️

✔️

✔️

ss2tf

ss2zpk

step

stft

N/A

N/A

N/A

sweep_poly

symiirorder1

symiirorder2

tf2sos

✔️

tf2ss

tf2zpk

✔️

unique_roots

✔️

unit_impulse

upfirdn

✔️

vectorstrength

✔️

✔️

welch

✔️

✔️

whittaker_henderson

wiener

✔️

✔️

zoom_fft

zpk2sos

✔️

zpk2ss

zpk2tf

✔️

Support with JIT#

Legend

✔️ = supported

✖ = unsupported

N/A = out-of-scope

function/class

jax

CZT

ShortTimeFFT

StateSpace

TransferFunction

ZerosPolesGain

ZoomFFT

abcd_normalize

✔️

argrelextrema

argrelmax

argrelmin

band_stop_obj

bessel

besselap

✔️

bilinear

bilinear_zpk

bode

buttap

✔️

butter

buttord

cheb1ap

✔️

cheb1ord

cheb2ap

✔️

cheb2ord

cheby1

cheby2

check_COLA

N/A

check_NOLA

chirp

choose_conv_method

✔️

closest_STFT_dual_window

coherence

cont2discrete

convolve

✔️

convolve2d

✔️

correlate

✔️

correlate2d

✔️

correlation_lags

N/A

csd

cspline1d

cspline1d_eval

cspline2d

czt

czt_points

dbode

decimate

deconvolve

detrend

✔️

dfreqresp

dimpulse

dlsim

dlti

dstep

ellip

ellipap

✔️

ellipord

envelope

✔️

fftconvolve

✔️

filtfilt

find_peaks

find_peaks_cwt

findfreqs

firls

firwin

firwin2

firwin_2d

freqresp

freqs

freqs_zpk

freqz

freqz_sos

freqz_zpk

✔️

gammatone

✔️

gauss_spline

✔️

gausspulse

get_window

✔️

group_delay

hilbert

✔️

hilbert2

✔️

iircomb

iirdesign

iirfilter

iirnotch

✔️

iirpeak

✔️

impulse

✔️

invres

invresz

istft

N/A

kaiser_atten

N/A

kaiser_beta

N/A

kaiserord

N/A

lfilter

lfilter_zi

lfiltic

lombscargle

lp2bp

lp2bp_zpk

lp2bs

lp2bs_zpk

lp2hp

lp2hp_zpk

lp2lp

lp2lp_zpk

lsim

lti

max_len_seq

medfilt

medfilt2d

minimum_phase

normalize

oaconvolve

✔️

order_filter

peak_prominences

peak_widths

periodogram

place_poles

qspline1d

qspline1d_eval

qspline2d

remez

resample

✔️

resample_poly

residue

residuez

savgol_coeffs

✔️

savgol_filter

sawtooth

sepfir2d

sos2tf

sos2zpk

sosfilt

sosfilt_zi

sosfiltfilt

sosfreqz

spectrogram

N/A

spline_filter

square

✔️

ss2tf

ss2zpk

step

stft

N/A

sweep_poly

symiirorder1

symiirorder2

tf2sos

tf2ss

tf2zpk

unique_roots

unit_impulse

upfirdn

vectorstrength

welch

✔️

whittaker_henderson

wiener

zoom_fft

zpk2sos

zpk2ss

zpk2tf