Utility function for mixAR

Extracts the (t-i)th component from a vector.

Usage

ui(x, t, i)

Arguments

x

A vector.

t

The present "time".

i

The lag. Can be a vector.

Value

Returns the (t-i)th element of the vector. If i=0, returns 1.

Author

Davide Ravagli

Note

This is a utility function for mixAR.