Access the perturbation delta of a Variable or Parameter

Used by psolve() with requires_grad = TRUE and Problem$derivative(). On a Parameter, the user sets delta to a perturbation of the parameter's value; derivative() then reports the predicted change in each Variable's optimal value as delta(variable).

Usage

delta(x)

delta(x) <- value

Arguments

x

A Variable or Parameter.

value

A numeric array of the same shape as x, or NULL.

Value

The perturbation (numeric array) or NULL.