init_dx: Initialise the dual component
Description
Initialise the dual component
Usage
init_dx(num_dim, denom_dim, num_ind)
Arguments
num_dim
A number; the length of the numerator of a derivative.
denom_dim
Numeric vector; the length of the denominators of a derivative.
num_ind
An integer that indicates the location of the derivative
corresponding to x; input -1 if none.
Value
A numeric matrix; the dual component.