Small R script to visualize bit differences between two disk images

diskdiffs.R

library(ggplot2)
library(scales)
library(plyr)
library(reshape2)

disk_errors <- read.csv("disk_errors.csv", header=F)
names(disk_errors) <- c("byte_offset", "bit", "a", "b")
disk_errors <- mutate(disk_errors,
                      bit = factor(bit),
                      track = floor(byte_offset / 256 / 16),
                      track_byte = byte_offset - track * 256 * 16,
                      track_sector = track_byte / 256)

qplot(track, track_sector, data = disk_errors, color = bit,
      shape = I("."), geom = "jitter", height = 0) +
  scale_y_continuous(breaks = 0:16) +
  opts(title = "Errors in round-trip image compared to original") +
  xlab("Track in disk image") +
  ylab("Logical position of byte error within track")

ggsave(file = "adtpro-round-trip-bit-errors.png")