Zahlenmauern

# i: row of Zahlenmauer
# j: j-th entry of Zahlenmauer

i_j_to_ii <- function(i, j) {
  ii <- 0
  if(i > 1) {
    ii <- ii + sum(1:(i - 1))
  }
  return(ii + j)
}

ii_to_i_j <- function(ii) {
  i <- findInterval(ii, cumsum(1:20)) + 1
  j <- ii - sum(1:(i - 1))
  return(c(i, j))
}

ii_to_i_j(8)

[1] 4 2

plot_zahlenmauer <- function() {
  par(mar = c(0, 0, 0, 0))
plot(0, type = 'n', xlim = c(0, 1), ylim = c(0, 1), axes = FALSE)
n <- 7
w <- 1 / n
result <- list()
result[[n]] <- sample(2, n, replace = TRUE)
for (i in (n - 1):1)
  result[[i]] <- result[[i + 1]][-1] + result[[i + 1]][-length(result[[i + 1]])]

result_c <- as.character(rev(unlist(result)))
ii <- sample(length(result_c), sum(1:(n - 1)))
result_c[ii] <- "____"
result_c_l <- list()
ii <- 0
for(i in n:1) {
  result_c_l[[i]] <- result_c[ii + (1:i)]
  ii <- ii + i
}


avg <- function(x) {
  (x[-1] + x[-length(x)]) / 2
}

(x <- seq(0, 1, by = w))




for (i in n:1) {
  (y <- c(1 - i * w, 1 - (i - 1) * w))
  text(avg(x), avg(y), result_c_l[[i]])
  x <- avg(x)
}

}

for(i in 1:10) plot_zahlenmauer()

pdf('~/Desktop/zahlenmauer.pdf', paper = 'A4')
for(i in 1:5) {
  plot_zahlenmauer()
}
dev.off()

quartz_off_screen 
                2