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armax

Created on Fri Jul 28 2017

@author: Giuseppe Armenise

Classes:

Name Description
Armax

Armax

Armax(
    G: TransferFunction,
    H: TransferFunction,
    *order_bounds: tuple[int, int],
    Vn: float | floating,
    y_id: ndarray,
    method: ICMethods = "AIC"
)

The AutoRegressive-Moving-Average with eXogenous inputs model is computed based on a recursive lest-square regression between the input data (U) and the measured output data (Y). As Y is noisy in practice, a white noise (E) is identified within the model. This model is designed to deal with potential time-delays between U and Y.

SIPPY implements an iterative procedure, with extit{iterative least-square regression} = ILLS.

The following equations summarize the equations involved in the model:

$$ Y = G.U + H.E

G = B / A H = C / A

A = 1 + a_1z^(-1) + ... + a_naz^(-na) B = b_1z^(-1-theta) + ... + b_nbz^(-nb-theta) C = c_1z^(-1) + ... + c_ncz^(-nc) $$

Parameters:

Name Type Description Default

G

TransferFunction

output response

required

H

TransferFunction

noise response

required

order_bounds

tuple[int, int]

extended range of the order of: - na_bounds: the common denominator - nb_bounds: the G numerator - nc_bounds: the H numerator - theta_bounds: the discrete theta in B

()

Vn

float | floating

The estimated error norm.

required

y_id

ndarray

The model output including non-identified outputs.

required

method

ICMethods

Method used of to attribute a performance to the model

'AIC'
References

https://ieeexplore.ieee.org/abstract/document/8516791