yulab.utils (version 0.2.3)

initial_cache: Cache intermediate data

Description

Utilities to cache intermediate data: initialize items, update items, remove items, and retrieve elements.

Usage

initial_cache()
get_cache()
rm_cache()
initial_cache_item(item)
get_cache_item(item)
rm_cache_item(item)
update_cache_item(item, elements, ttl = NULL)
get_cache_element(item, elements, default = NULL, prune_expired = TRUE)
prune_cache_item(item)
cache_list_items()
cache_size()
cache_save(path)
cache_load(path)
with_cache(item, key, compute, ttl = NULL)

Value

Cache environment, item, or selected elements

Arguments

item

Cache item name

elements

Elements to cache

ttl

Time-to-live in seconds

default

Default value if cache element is missing

prune_expired

Logical, whether to prune expired items

path

File path to save or load cache

key

Element key

compute

Function to compute value when missing

Examples

if (FALSE) {
 slow_fib <- function(x) {
     if (x < 2) return(1)
     slow_fib(x-2) + slow_fib(x-1)
 }
 
 fast_fib <- function(x) {
     if (x < 2) return(1)
     res <- get_cache_element('fibonacci', as.character(x))
     if (!is.null(res)) {
         return(res)
     }
     res <- fast_fib(x-2) + fast_fib(x-1)
     e <- list()
     e[[as.character(x)]] <- res
     update_cache_item('fibonacci', e)
     return(res)
 }

 system.time(slow_fib(30))
 system.time(fast_fib(30)) 
    
 }