food-combinations-xkcd-1609

# Inspired by http://xkcd.com/1609/

set.seed(1609)
food <- c("ice cream", "ham", "relish",
          "pancakes", "ketchup", "cheese",
          "eggs", "cupcakes", "sour cream",
          "hot chocolate", "avocado", "skittles",
          "wasabi", "tofu", "steak", "sweet potatoes")
nfood <- length(food)

food_combination <- function(x) {
  i <- sample(1:nfood, 1)
  t_food <- food[-i]
  j <- sample(1:length(t_food), 1)
  f1 <- food[i]
  f2 <- t_food[j]
  sprintf("(%d) You know what's actually really good? %s and %s", x, f1, f2)
}

sapply(1:10, "food_combination")

food-combinations2-xkcd-1609

# a variation that shows the frequency of combinations
set.seed(1609)
food <- c("ice cream", "ham", "relish",
          "pancakes", "ketchup", "cheese",
          "eggs", "cupcakes", "sour cream",
          "hot chocolate", "avocado", "skittles",
          "wasabi", "tofu", "steak", "sweet potatoes")
nfood <- length(food)

food_combination2 <- function(x) {
  i <- sample(1:nfood, 1)
  t_food <- food[-i]
  j <- sample(1:length(t_food), 1)
  f1 <- food[i]
  f2 <- t_food[j]
  c(food1=f1, food2=f2)
}

combos <- as.data.frame(t(sapply(1:10000, "food_combination2")))
combos_freq <- as.data.frame(table(combos$food1, combos$food2))
library(ggplot2)
ggplot(combos_freq, aes(Var1, Var2)) +
  geom_tile(aes(fill=Freq), colour="white") +
  scale_fill_gradient(low = "white", high="red")

# Some combinations are interesting like "eggs and wasabi" or "sweet potatoes and sourcream", others are
# marginal like "cheese and skittles"