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roots computes the roots of lag polynomials from polynomial objects and time series models that contain lag polynomials as components.
roots
roots(x, ...)# S3 method for default roots(x, ...)# S3 method for lagpol roots(x, table = TRUE, tol = 1e-05, ...)# S3 method for tf roots(x, opr = c("arma", "ar", "ma"), ...)# S3 method for um roots(x, opr = c("arma", "ar", "ma", "i", "arima"), ...)
# S3 method for default roots(x, ...)
# S3 method for lagpol roots(x, table = TRUE, tol = 1e-05, ...)
# S3 method for tf roots(x, opr = c("arma", "ar", "ma"), ...)
# S3 method for um roots(x, opr = c("arma", "ar", "ma", "i", "arima"), ...)
Returns a summary table with the roots of each lagpol.
lagpol
A model object containing lag polynomials ("um", "tfm") or a lag polynomial object ("lagpol").
Additional arguments passed to methods.
Logical. If TRUE returns detailed table, if FALSE complex vector.
Tolerance for identifying distinct roots.
character. Operators for which roots are computed. Options: "arma", "arma", "ar", "ma", "i" or "arima".
roots(c(1, 1.2, -0.8)) um1 <- um(ar = "(1 - 0.8B)(1 - 0.8B^12)") roots(um1)
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