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Create wind rose diagrams

Source: R/plotting_wind_rose.R
wind_rose.Rd

Generates polar bar charts (wind roses) that summarise the joint distribution of wind speed and direction. Bars are stacked by wind speed category and oriented toward the compass direction from which the wind originates.

Usage

wind_rose(
  obs,
  data_cols = c(ws = "ws_1hr", wd = "wd_1hr"),
  facet_by = NULL,
  facet_rows = 1,
  wd_nbins = c(16, 8, 4)[1],
  freq_labels_position = NULL,
  ws_min = 0,
  ws_step = 2,
  ws_out_units = "m/s",
  fills = "default",
  colour = "black",
  alpha = 0.8,
  bar_width = 1,
  show_missing = TRUE,
  ...
)

Arguments

obs

A data frame with at least the columns named in `data_cols` and, when supplied, `facet_by`. Must contain at least one row.

data_cols

A named character vector of length 2 mapping the logical roles `"ws"` (wind speed) and `"wd"` (wind direction) to column names in `obs`. Defaults to `c(ws = "ws_1hr", wd = "wd_1hr")`.

facet_by

A character vector of one or two column names in `obs` used as faceting variables in [ggplot2::facet_wrap()]. Names, if present, are used as strip labels. Defaults to `NULL` (no faceting).

facet_rows

A single positive integer giving the number of rows in the facet layout. Ignored when `facet_by` is `NULL`. Defaults to `1`.

wd_nbins

Number of directional bins. Must be one of `16` (N, NNE, NE, ENE, …), `8` (N, NE, E, SE, …), or `4` (N, E, S, W). Defaults to `16`.

freq_labels_position

A single numeric value in \[0, 360\] specifying the compass bearing (degrees) at which the frequency-axis labels are placed. Values are snapped to the nearest cardinal direction. Defaults to `NULL`, which places labels at the least busy cardinal direction.

ws_min

Minimum wind speed to include. Observations below this threshold are dropped before plotting. Units are inferred from the data or from `ws_out_units`. Defaults to `0`.

ws_step

Width of each wind speed bin in the units given by `ws_out_units`. Defaults to `2`.

ws_out_units

A single character string specifying the output units for wind speed (e.g. `"m/s"`, `"km/h"`, `"mph"`). When the wind speed column does not carry unit metadata it is assumed to be in m/s and converted as needed. Defaults to `"m/s"`.

fills

A character vector of colours for the wind speed fill scale. Should have at least as many values as there are wind speed bins. Pass `"default"` to use [ggplot2::scale_fill_viridis_d()]. Defaults to `"default"`.

colour

A single character string giving the colour used for bar outlines. Defaults to `"black"`.

alpha

A single numeric value in \[0, 1\] controlling the opacity of the bar fills. `0` is fully transparent; `1` is fully opaque. Defaults to `0.8`.

bar_width

A single numeric value in \[0, 1\] controlling the relative width of each directional bar. A value of `1` makes adjacent bars touch. Defaults to `1`.

show_missing

A single logical value indicating whether to display a text label of the proportion of observations missing a wind direction or wind speed. Defaults to `TRUE`.

...

Additional arguments passed to [ggplot2::geom_col()], such as `linewidth` or `linetype`.

Value

A [ggplot2::ggplot()] object.

See also

Other Data Visualisation: taylor_diagram(), tile_plot()

Examples

if (FALSE) { # \dontrun{

# Basic usage
wind_rose(example_obs)

# Coarser 8-point rose with output in km/h
wind_rose(example_obs, wd_nbins = 8, ws_out_units = "km/h", ws_step = 10)
} # }