xdas.atoms.Sequential

class xdas.atoms.Sequential(atoms: Any, name: str | None = None)

A class to handle a sequence of operations.

Each operation is represented by an Atom class object, which contains the function and its arguments. Sequence inherits from list, and therefore behaves as it.

Parameters:

• atoms (list) – The sequence of operations. Each element must either be an Atom, a Sequence, or an unitary callable.

• name (str) – A label given to this sequence.

Examples

>>> from xdas.atoms import Partial, Sequential
>>> import xdas.signal as xs
>>> import numpy as np

Basic usage:

>>> seq = Sequential(
...     [
...         Partial(xs.taper, dim="time"),
...         Partial(xs.lfilter, [1.0], [0.5], ..., dim="time", zi=...),
...         Partial(np.square),
...     ],
...     name="Low frequency energy",
... )
>>> seq
Low frequency energy:
  0: taper(..., dim=time)
  1: lfilter([1.0], [0.5], ..., dim=time)  [stateful]
  2: square(...)

Nested sequences:

>>> seq = Sequential(
...     [
...         Partial(xs.decimate, 16, dim="distance"),
...         seq,
...     ]
... )
>>> seq
Sequence:
  0: decimate(..., 16, dim=distance)
  1:
    Low frequency energy:
      0: taper(..., dim=time)
      1: lfilter([1.0], [0.5], ..., dim=time)  [stateful]
      2: square(...)

Applying the sequence to data:

>>> from xdas.synthetics import wavelet_wavefronts
>>> da = wavelet_wavefronts()
>>> seq(da)
<xdas.DataArray (time: 300, distance: 26)>
[[0.000000e+00 0.000000e+00 0.000000e+00 ... 0.000000e+00 0.000000e+00
  0.000000e+00]
 [5.925923e-10 3.640952e-11 1.315744e-11 ... 4.024388e-14 3.245748e-12
  7.679807e-12]
 [3.497487e-09 1.191342e-10 4.021543e-11 ... 7.463132e-12 9.458801e-11
  2.833292e-10]
 ...
 [2.331440e-08 5.785383e-10 4.336722e-11 ... 1.827452e-11 5.099163e-10
  1.320907e-09]
 [1.826236e-09 5.470673e-11 1.045146e-11 ... 1.561169e-13 3.063598e-14
  7.832009e-16]
 [0.000000e+00 0.000000e+00 0.000000e+00 ... 0.000000e+00 0.000000e+00
  0.000000e+00]]
Coordinates:
  * time (time): 2023-01-01T00:00:00.000 to 2023-01-01T00:00:05.980
  * distance (distance): 0.000 to 10000.000

__init__(atoms: Any, name: str | None = None) → None

Methods

__init__(atoms[, name])
append(object, /)	Append object to the end of the list.
call(x, **flags)	Pass x through each atom in order and return the final result.
clear()	Remove all items from list.
copy()	Return a shallow copy of the list.
count(value, /)	Return number of occurrences of value.
extend(iterable, /)	Extend list by appending elements from the iterable.
index(value[, start, stop])	Return first index of value.
initialize(x, **flags)	Initialise the atom from a first chunks of data.
initialize_from_state()	Initialise the atom from its current state.
insert(index, object, /)	Insert object before index.
load_state(path)	Load the atom state from the NetCDF4 file at path.
pop([index])	Remove and return item at index (default last).
remove(value, /)	Remove first occurrence of value.
reset()	Reset the state of all stateful atoms in the sequence.
reverse()	Reverse IN PLACE.
save_state(path)	Serialise the current state to a NetCDF4 file at path.
set_state(state)	Restore the atom state from a previously saved state dict.
sort(*[, key, reverse])	Sort the list in ascending order and return None.

Attributes

initialized	True if every state key has been initialised (no ... sentinels remain).
state	Dict of the current state, including nested atom states.