Reduction chain-rule hooks (backward / forward, parameter / variable)

Reduction chain-rule hooks (backward / forward, parameter / variable)

Usage

param_backward(x, param, dparams)

param_forward(x, param, delta)

var_backward(x, var, value)

var_forward(x, var, value)

Arguments

x

A Reduction.

param

A Parameter from the original problem.

dparams

Named list of param-id -> gradient arrays for the reduced (transformed) parameters.

delta

Numeric array of perturbations to the original param.

var

A Variable from the original problem.

value

Numeric array (gradient or delta) attached to var.

Value

A gradient array for param, or NULL if this reduction does not touch param.

Named list of transformed-param-id -> delta arrays, or NULL if this reduction does not touch param.