atime (version 2025.4.1)

atime_grid: Asymptotic timing grid

Description

Create expressions for asymptotic timing by substituting values into expressions.

Usage

atime_grid(
  param.list = list(), 
  ...,
  name.value.sep="=",
  expr.param.sep=" ",
  collapse = ",", 
  symbol.params=character())

Value

Named list of expressions which can be used as expr.list

argument of atime.

Arguments

param.list

Named list of items to replace in ... expressions, default empty list means nothing to replace.

...

Named expressions which each must contain each name of param.list.

name.value.sep

string: separator between names and values from param.list, default "=".

expr.param.sep

string: separator between expressions and parameters, default " ".

collapse

string: separator between parameters, default ",".

symbol.params

character vector: these elements of param.list will be converted to symbols before substitution.

Author

Toby Dylan Hocking

Examples

data.table::setDTthreads(1) # for CRAN.

## Example 0: with no param.list, same as quote inside named list.
atime::atime_grid(m=mean(data), s=sum(data))
list(m=quote(mean(data)), s=quote(sum(data)))

## Example 1: polynomial vs exponential time regex.
(expr.list <- atime::atime_grid(
  list(PERL=c(TRUE, FALSE)),
  expr.param.sep="\n",
  regexpr=regexpr(pattern, subject, perl=PERL)))
atime.list <- atime::atime(
  seconds.limit=0.001,
  N=unique(as.integer(10^seq(0,2,l=30))),
  setup={
    subject <- paste(rep("a", N), collapse="")
    pattern <- paste(rep(c("a?", "a"), each=N), collapse="")
  },
  expr.list=expr.list)
plot(atime.list)

## Example 2: symbol.params arg.
sub.param.list <- list(FUN=c("sub","gsub"), PERL=c(TRUE,FALSE))
## with base R we can use as.symbol and substitute:
sapply(sub.param.list$FUN,function(name)substitute(fun("a","",subject), list(fun=as.symbol(name))))
## with atime_grid the analog is to use symbol.params argument:
(sub.expr.list <- atime::atime_grid(
  sub.param.list,
  replace=FUN("a","",subject,perl=PERL),
  symbol.params="FUN"))
sub.atime.list <- atime::atime(
  seconds.limit=0.001,
  setup={
    subject <- paste(rep("a",N),collapse="")
  }, 
  expr.list=sub.expr.list)
plot(sub.atime.list)

## Customize ggplot, which shows expr.name column as direct labels.
sub.atime.edited <- sub.atime.list
library(data.table)
sub.atime.edited$measurements <- data.table(sub.atime.list$measurements)[
, expr.name := paste0("PERL=",PERL)]
if(require(ggplot2)){
  plot(sub.atime.edited)+
    facet_grid(unit ~ FUN, labeller=label_both)
}