rose des vents

Code R de l'exemple ggplot2

library(ggplot2)
library(dplyr)
library(openair)

## Hourly wind at Marylebone Road, London, 1998-2005: share of the hours by
## direction (eight sectors) and by speed class.
winds <- mydata |>
  filter(!is.na(wd), !is.na(ws), ws > 0) |>
  mutate(sector = factor(c("N", "NE", "E", "SE", "S", "SW", "W", "NW")[((wd + 22.5) %% 360) %/% 45 + 1],
                         levels = c("N", "NE", "E", "SE", "S", "SW", "W", "NW")),
         speed = cut(ws, c(0, 2, 4, 6, Inf), labels = c("0–2", "2–4", "4–6", "6+"), ordered_result = TRUE)) |>
  count(sector, speed) |>
  mutate(share = 100 * n / sum(n))

p <- ggplot(winds, aes(x = sector, y = share, fill = speed)) +
  geom_col(width = 0.9, colour = "white", linewidth = 0.2) +
  coord_radial(start = -pi / 8, expand = FALSE) +
  scale_fill_ordinal(type = idest_seq[c(1, 3, 4, 6)], name = "Wind speed (m/s)") +
  scale_y_continuous(labels = \(x) paste0(lex_number(x), "%")) +
  labs(title = "South-west winds were the commonest and fastest",
       subtitle = "Share of hours by direction, Marylebone Road, London, 1998–2005",
       x = NULL, y = NULL,
       caption = "Data: London Air Quality Network, via the openair R package") +
  theme_lex_viz(grid = "xy", arrows = "") +
  theme(legend.position = "right")