Napoleon hành quân tới Mạc Tư Khoa (1812)

libs <- c("ggplot2", "HistData", "scales")
lapply(libs, require, character.only = TRUE)

## Loading required package: ggplot2
## Loading required package: HistData
## Loading required package: scales

## [[1]]
## [1] TRUE
## 
## [[2]]
## [1] TRUE
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## [[3]]
## [1] TRUE

(plot_troops <- ggplot(Minard.troops, aes(long, lat)) +
  geom_path(aes(size = survivors, color = direction,
                group = group)))

(plot_both <- plot_troops +
  geom_text(aes(label = city), size = 4, data = Minard.cities))

(plot_polished <- plot_both +
  scale_size(range = c(1, 10),
             breaks = c(1, 2, 3) * 10^5,
             labels = comma(c(1, 2, 3) * 10^5)) +
  scale_color_manual(values = c("grey50","red")) +
  xlab(NULL) +
  ylab(NULL))