lagpol0: Create lag polynomial objects

In tfarima: Transfer Function and ARIMA Models

Create lag polynomial objects

Description

'lagpol0' is a flexible constructor for lagpol objects. It accepts multiple input formats: polynomial orders (d, s, p), literal equations (e.g., 1 - 0.8B), or seasonal specifications for special lag polynomials like AR/I/MA(s-1).

Usage

lagpol0(op, type, envir = parent.frame())

Arguments

op	Polynomial specification in one of these formats: Numeric vector c(d, s, p) specifying polynomial degree, lag step (default 1), and exponent (default 1) Character equation (e.g., "1 - 0.8B") Seasonal period or frequency (e.g., "12" or "1/12") List combining multiple specifications
type	Operator type: "ar" (autoregressive), "ma" (moving average), or "i" (integration).
envir	Environment for argument evaluation. Defaults to parent frame.

Value

List of lagpol objects.

See Also

lagpol

Examples

# AR(1) polynomial
lagpol0(op = 1, type = "ar")

# From literal equation
lagpol0(op = "1 - 0.8B", type = "ar")

# Multiple polynomials at once
lagpol0(op = list(1, "1 - 0.5B"), type = "ma")

# Seasonal polynomial
lagpol0(op = "12", type = "ar")

# Custom orders with seasonal component
lagpol0(op = c(2, 12, 1), type = "ar")

tfarima documentation built on Nov. 5, 2025, 7:43 p.m.