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Data Generation for Circles

Source: R/circle_data.R
circle_data.Rd

A tool for creating a data frame of values that create a circle with a specified radius when plotted.

The geom_path and geom_polygon geoms are recommended with this data for use in ggplot2 for generative art.

Usage

circle_data(
  x,
  y,
  radius,
  color = NULL,
  fill = NULL,
  n_points = 100,
  group_var = FALSE,
  group_prefix = "circle_"
)

Arguments

x

Numeric value of length 1 - The center x coordinate value of the circle.

y

Numeric value of length 1 - The center y coordinate value of the circle.

radius

Numeric value of length 1 that must be greater than 0 - The radius of the circle.

color

Character value of length 1 - The color of the square's border. A valid R color from colors() or a standard 6 digit hexadecimal webcolor like "#000000"

fill

Character value of length 1 - The color of the square. A valid R color from colors() or a standard 6 digit hexadecimal webcolor like "#000000"

n_points

Numeric value. Default is 100. This determines how many points the square will have. This option can come in handy when using jitter options or other texture/illusion methods. Must be of length 1 and at least a value of 100.

group_var

Logical. Default is FALSE. If TRUE, a group variable will be added to the dataframe. Useful in iterative data generation.

group_prefix

Character string of length 1 - The prefix used for the group variable. Default is "square_"

Value

A Tibble

Examples

# Creating one circle

library(ggplot2)
one_circle <- circle_data(x = 0, y = 0, radius = 5)

# Plot The Data
one_circle |>
  ggplot(aes(x, y)) +
  geom_path(color = "green") +
  coord_equal()


# To create multiple circles, use your preferred method of iteration:
# Creating two circles

library(purrr)
library(dplyr)
#> 
#> Attaching package: ‘dplyr’
#> The following objects are masked from ‘package:stats’:
#> 
#>     filter, lag
#> The following objects are masked from ‘package:base’:
#> 
#>     intersect, setdiff, setequal, union

# Make your specs
x_vals <- c(0, 10)
y_vals <- c(0, 0)
radi <- c(1, 3)
fills <- c("purple", "yellow")
circle_n <- 1:2

# Prep for your iteration
lst_circle_specs <-
  list(
    x_vals,
    y_vals,
    radi,
    fills,
    circle_n
  )

# Use `circle_data()` in your preferred iteration methods
two_circles <- pmap(lst_circle_specs, ~ circle_data(
  x = ..1,
  y = ..2,
  radi = ..3,
  fill = ..4,
  color = "#000000",
  group_var = TRUE
) |>
  # circle_data adds a `group` variable if `group_var` = TRUE.
  # For multiple circles, a unique identifier should be added/pasted in.
  mutate(group = paste0(group, ..5))) |>
  list_rbind()

# Plot the data

two_circles |>
  ggplot(aes(x, y, group = group)) +
  theme(legend.position = "none") +
  geom_polygon(
    color = two_circles$color,
    fill = two_circles$fill
  ) +
  coord_equal() #Always use coord_equal() or coord_fixed for circles!