jaye-ross

"""
Bucket sort (of type List[int])
"""

from itertools import chain
from typing import List

def bucket_sort(somelist: List[int], n_buckets: int = None, approximate: bool = False):
    if n_buckets is None:
        n_buckets = int(len(somelist) ** 0.5)

jaye-ross

;; stauf painting problem

(defn get-move [x]
  (case x
    0 '(1 1 0
        1 1 0
        0 0 0)
    1 '(1 1 1
        0 0 0
        0 0 0)

jaye-ross

;; see https://www.quantamagazine.org/mathematician-terence-tao-and-the-collatz-conjecture-20191211/
;; for problem statement and definition of the sequence

(defn collatz [x]
	(if (even? x) (/ x 2) (+ (* x 3) 1)))

(defn collatz-seq [x]
	(lazy-cat [x] (collatz-seq (collatz x))))

;; test

jaye-ross

#lang racket

(define (values-in-row pz row)
  (filter
   identity
   (map
    (lambda (col)
      (let ([key (list row col)])
        (if (hash-has-key? pz key)
            (hash-ref pz key)

jaye-ross

#lang racket

(define (next-value current-value)
  (if (= current-value 0)
      (if (= (random 2) 0) '(1) '(1 0))
      '(0 1)))

(define (do-sub myl)
  (apply append
         (map next-value myl)))

jaye-ross

; things are looking up; you might see the solution in your lifetime

(def digits (range 9))

(defn find-open-position [puzzle]
  (first 
    (remove nil? 
            (for [i digits j digits] 
              (cond (nil? (puzzle [i j])) [i j] 
                    :else nil)))))

jaye-ross

;; I think technically this works, but the algorithm is very slow and you won't see the solution in your lifetime.

(def digits (range 9))

(defn find-open-position [puzzle]
  (first 
    (remove nil? 
            (for [i digits j digits] 
              (cond (nil? (puzzle [i j])) [i j] 
                    :else nil)))))

jaye-ross

library(tidyverse)

dist = function(v1,v2) {
  sqrt(sum((v1-v2)^2))
}

# point and mu are numerical vectors of the same length
sum_of_squares = function(point,mu){
  sum((point - mu)^2)
}

jaye-ross

# https://en.wikipedia.org/wiki/Partition_of_a_set#Counting_partitions

bell = function(n) {
  ifelse(n > 0,
         sum(Vectorize(function(n, k) {
           choose(n - 1, k) * bell(k)
         }, "k")(n, 0:(n - 1))),
         1)
}

jaye-ross

#

add = function(a,b,add_func="add_func"){
  add_func(a,b)
}

# 0,1 with addition mod 2
add_func = function(a,b){
  (a + b) %% 2
}