dual {ADtools}

R Documentation

Dual number constructor

Description

Dual number constructor

Usage

dual(x, param_dim, ind)

Arguments

x	The object to be converted to a dual number.
param_dim	A named list. The dimension of the dual component to be attached.
ind	Integer; the index in 'param_dim' corresponding to 'x'. Use '-1' if it is not applicable.

Value

A dual number with components "x" and "dx". The first gives the value of 'f', and the second gives the derivative of 'f'.

Examples

# Suppose X is a 2 x 2 matrix, Y is a 3 x 1 vector, Z is a 2 x 3 matrix, and
# we wish to attach dual components {dX, dY, dZ} to X.
dual(randn(2, 2), list(X = 4, Y = 3, Z = 6), ind = 1)

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