torch (version 0.8.0)

lr_lambda: Sets the learning rate of each parameter group to the initial lr times a given function. When last_epoch=-1, sets initial lr as lr.

Description

Sets the learning rate of each parameter group to the initial lr times a given function. When last_epoch=-1, sets initial lr as lr.

Usage

lr_lambda(optimizer, lr_lambda, last_epoch = -1, verbose = FALSE)

Arguments

optimizer

(Optimizer): Wrapped optimizer.

lr_lambda

(function or list): A function which computes a multiplicative factor given an integer parameter epoch, or a list of such functions, one for each group in optimizer.param_groups.

last_epoch

(int): The index of last epoch. Default: -1.

verbose

(bool): If TRUE, prints a message to stdout for each update. Default: FALSE.

Examples

if (torch_is_installed()) {
# Assuming optimizer has two groups.
lambda1 <- function(epoch) epoch %/% 30
lambda2 <- function(epoch) 0.95^epoch
if (FALSE) {
scheduler <- lr_lambda(optimizer, lr_lambda = list(lambda1, lambda2))
for (epoch in 1:100) {
  train(...)
  validate(...)
  scheduler$step()
}
}

}