I need to create a knight tour plot out of such an exemplary matrix:
Mat = matrix(c(1, 38, 55, 34, 3, 36, 19, 22,
54, 47, 2, 37, 20, 23, 4, 17,
39, 56, 33, 46, 35, 18, 21, 10,
48, 53, 40, 57, 24, 11, 16, 5,
59, 32, 45, 52, 41, 26, 9, 12,
44, 49, 58, 25, 62, 15, 6, 27,
31, 60, 51, 42, 29, 8, 13, 64,
50, 43, 30, 61, 14, 63, 28, 7), nrow=8, ncol=8, byrow=T)
Numbers indicate the order in which knight moves to create a path. I have a lot of these kind of results with chessboard up to 75 in size, however I have no way of presenting them in a readable way, I found out that R, given the matrix, is capable of creating a plot like this: link (this one is 50x50 in size)
So for the matrix I presented the lines between two points occur between the numbers like: 1 - 2 - 3 - 4 - 5 - ... - 64, in the end creating a path presented in the link, but for the 8x8 chessboard, instead of 50x50
However, I have a very limited time to learn R good enough to accomplish it, I am desperate for any kind of direction. How hard does creating such code in R, that tranforms any matrix into such plot, is going to be ? Or is it something trivial ? Any code samples would be a blessing
You can use geom_path as described here: ggplot2 line plot order
In order to do so you need to convert the matrix into a tibble.
coords <- tibble(col = rep(1:8, 8),
row = rep(1:8, each = 8))
coords %>%
mutate(order = Mat[8 * (col - 1) + row]) %>%
arrange(order) %>%
ggplot(aes(x = col, y = row)) +
geom_path() +
geom_text(aes(y = row + 0.25, label = order)) +
coord_equal() # Ensures a square board.
You can subtract .5 from the col and row positions to give a more natural chess board feel.