lr_lambda function

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.

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
## Not run:

scheduler <- lr_lambda(optimizer, lr_lambda = list(lambda1, lambda2))
for (epoch in 1:100) {
  train(...)
  validate(...)
  scheduler$step()
}
## End(Not run)

}