scipy.signal.lfiltic#
- scipy.signal.lfiltic(b, a, y, x=None)[source]#
Construct initial conditions for lfilter given input and output vectors.
Given a linear filter (b, a) and initial conditions on the output y and the input x, return the initial conditions on the state vector zi which is used by
lfilter
to generate the output given the input.- Parameters:
- barray_like
Linear filter term.
- aarray_like
Linear filter term.
- yarray_like
Initial conditions.
If
N = len(a) - 1
, theny = {y[-1], y[-2], ..., y[-N]}
.If y is too short, it is padded with zeros.
- xarray_like, optional
Initial conditions.
If
M = len(b) - 1
, thenx = {x[-1], x[-2], ..., x[-M]}
.If x is not given, its initial conditions are assumed zero.
If x is too short, it is padded with zeros.
- Returns:
- zindarray
The state vector
zi = {z_0[-1], z_1[-1], ..., z_K-1[-1]}
, whereK = max(M, N)
.
See also