MartinMSPedersen

x <- function(k, t) {

  c(     -sin(4*pi*k/1000) + sin(t)*sin(t/3)/5,
     -0.5*sin(8*pi*k/1000) + cos(t)/2
  )
}

y <- function(k, t) {
  c(     -cos(2*pi*k/1000) + cos(t)*cos(t/3)/2,
     -0.5*cos(4*pi*k/1000) + sin(t)/3

MartinMSPedersen

library(ggplot2)

hexdf <- function (size = 1, mid = c(0, 0), angle = 90) {
  width <- size * 1
  height <- size * 0.865
  xy <- shape:::getellipse(width, height, mid = mid, dr = 2 * pi/6)
  tibble::as_tibble(structure(as.data.frame(
    shape::rotatexy(xy,angle = angle, mid = mid)), class = "data.frame", names = c("x", "y")), validate = FALSE)
}

MartinMSPedersen

#  Yavalath board

library(ggplot2)

hexdf <- function (size = 1, mid = c(0, 0), angle = 90) {
  width <- size * 1
  height <- size * 0.865
  xy <- shape:::getellipse(width, height, mid = mid, dr = 2 * pi/6)
  tibble::as_tibble(structure(as.data.frame(
    shape::rotatexy(xy,angle = angle, mid = mid)), class = "data.frame", names = c("x", "y")), validate = FALSE)

MartinMSPedersen

circleFunc <- 
  function(center = c(0,0), diameter = 1, npoints = 100, start = 0, end = 2*pi) {
    tt <- seq(start, end, length.out = npoints)
    data.frame(x = center[1] + diameter / 2 * cos(tt),
               y = center[2] + diameter / 2 * sin(tt))
  }

add.alpha <- function(col, alpha = 1) {
	if(missing(col))
		stop("Please provide a vector colors.")

MartinMSPedersen

library(ggplot2)

circle_alpha <- 0.3
radius1 <- 25
radius2 <- 75
how_many <- 200
reverse_colors <- FALSE

circleFunc <-
  function(center = c(0,0), radius = 1, npoints = 100, start = 0, end = 2*pi) {

MartinMSPedersen

polygon <- function(n) {
  tibble(
    x    = accumulate(1:(n-1), ~.x+cos(.y*2*pi/n), .init = 0),
    y    = accumulate(1:(n-1), ~.x+sin(.y*2*pi/n), .init = 0),
    xend = accumulate(2:n,     ~.x+cos(.y*2*pi/n), .init = cos(2*pi/n)),
    yend = accumulate(2:n,     ~.x+sin(.y*2*pi/n), .init = sin(2*pi/n)))
}

ggplot(polygon(5) + geom_segment(aes(x=x, y=y, xend=xend, yend=yend)) + theme_void() + coord_equal()

MartinMSPedersen

Flipping Business Card

Inspired by @lauraalpinto: https://codepen.io/lauraalpinto/pen/qLzGBX?editors=0100

A Pen by Martin Møller Skarbiniks Pedersen on CodePen.

License.

MartinMSPedersen

library(gmp)

ONE <- as.bigz("1")
TWO <- as.bigz("2")
THREE <- as.bigz("3")
FOUR <- as.bigz("4")
SEVEN <- as.bigz("7")
TEN <- as.bigz("10")

q <- as.bigz("1")

MartinMSPedersen

#http://rosettacode.org/wiki/Generate_Chess960_starting_position

pieces <- c("R","B","N","Q","K","N","B","R")

generateFirstRank <- function() {
  attempt <- paste0(sample(pieces), collapse = "")
  while (!check_position(attempt)) {
    attempt <- paste0(sample(pieces), collapse = "")
  }
  return(attempt)

MartinMSPedersen

library(digest)

DEBUG <- FALSE

while(TRUE) {
  flag <- paste0(c(sample(c(letters,LETTERS,0:9,":","_","+"), 8, replace = TRUE)), collapse = "")

  shasum <- substr(digest(flag,"md5", serialize=FALSE), 27,32)
  cat(flag,shasum,"\n")
}