TobCap

R language tail (call|recursion) (optimization|elimination)

List of packages or documents

URL	type	author (twitter)	depends on	note
trampoline	package	@ecologician	coro, fastmap, rlang
rcompilertools (tweet post)	package	@dirk_sch	compiler, utils, tibble	byte compiler
tailr

TobCap

R-lang combinator manipulation

• This is forked and summarized from https://github.com/TobCap/R/blob/774e60bff9805b37fd791ca40cc1b9d435c8dd19/functional_programming.r#L477-L516
• Before starting, execute bottom part of self-build functions

Y combinator

http://en.wikipedia.org/wiki/Fixed-point_combinator

compare below this R's expression with the Y combinator definition written in wikipedia!

TobCap

調査目的

Windows 10 laptop の価格を比較

調査時点

2020/05/24

背景

Windows 10 WSL2 で NDIVIA GeForce を動かしたい。RAM 32GB 限定

条件

TobCap

# Original is https://gist.github.com/msakai/e39c25930b661e8175759cc15175d952
# Forked at 2020-01-09

# Attempt to mimick following GADT (Generalized algebraic data type) in Python:
#
# data Expr a where
#     Const :: a  -> Expr a
#     Add :: Expr Int -> Expr Int -> Expr Int
#     Eq :: Expr Int -> Expr Int -> Expr Bool
#     IfThenElse :: Expr Bool -> Expr a -> Expr a -> Expr a

TobCap

import asyncio
from time import time

async def slow_a():
    print("a start")
    await asyncio.sleep(2.5)
    print("a end")

async def slow_b():
    print("b start")

TobCap

library(tidyverse)

A <- data.frame(x = 1:3, y = letters[1:3], stringsAsFactors = FALSE)
shape <- matrix(1, 2, 3)

rep_df <- function(df_, shape) {
  df_ %>% 
    list() %>% 
    matrix %>% 
    kronecker(shape, FUN = rep.int) %>% 

TobCap

# Copyright(c) 2018 @tobakucptlsm
# Released under the MIT license
# http://opensource.org/licenses/mit-license.php

Gm911|Em911|Fm79/Bb|=|
Gm911|Em911|EbM7913|=|
Gm911======Em911|=|
Fm7911|====_Gbm7911_Gm911|
=======Em911|=======EbM7913|
=|=|

TobCap

Sys.setenv(LANG="C") # for english error message　on Windows
library(tidyverse)
#> Warning: package 'tidyverse' was built under R version 3.4.4
#> Warning: package 'tibble' was built under R version 3.4.4
#> Warning: package 'tidyr' was built under R version 3.4.4

#sessionInfo()
#with(R.version, print(c(platform, version.string)))

TobCap

MulLayer <- function(){
  x_ <- NA
  y_ <- NA

  forward <- function(x, y){
    x_ <<- x
    y_ <<- y
    x * y
  }
  

TobCap

$ python --version
Python 3.6.0 :: Anaconda 4.3.1 (x86_64)
$ python -c "import pandas as pd; print(pd.__version__)"
0.19.2
$ python
Python 3.6.0 |Anaconda 4.3.1 (x86_64)| (default, Dec 23 2016, 13:19:00) 
[GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.57)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> exam1(False)
rise_error=False