Draw a basis on a static ggplot — draw

Additively draws a basis on a static ggplot. Not a geom or proto. Expects

draw_basis(
  basis,
  map_to = data.frame(x = c(0, 1), y = c(0, 1)),
  position = c("left", "center", "right", "bottomleft", "topright", "off"),
  manip_col = "blue",
  line_size = 0.6,
  text_size = 4,
  basis_label = abbreviate(gsub("[^[:alnum:]=]", "", rownames(basis), 3L))
)

Arguments

basis: A (p*d) basis to draw. Draws the first two components. If facet is used cbind the facet variable to a specific facet level (2nd example), otherwise the basis prints on all facet levels.
map_to: A data.frame to scale the basis to. Defaults to a unitbox; data.frame(x = c(0,1), y = c(0,1)).
position: The position, to place the basis axes relative to the centered data. _basis Expects one of c("left", "center", "right", "bottomleft", "topright", "off"), defaults to "left".
manip_col: The color to highlight the manipulation variable with. Not applied if the tour isn't a manual tour. Defaults to "blue".
line_size: (2D bases only) the thickness of the lines used to make the axes and unit circle. Defaults to 0.6.
text_size: Size of the text label of the variables. Defaults to 4.
basis_label: The text labels of the data variables. Defaults to the 3 character abbreviation of the rownames of the basis.

Examples

library(spinifex)
library(ggplot2)
#> 
#> Attaching package: 'ggplot2'
#> The following objects are masked from 'package:spinifex':
#> 
#>     scale_colour_discrete, scale_fill_discrete
dat  <- scale_sd(penguins_na.rm[, 1:4])
clas <- penguins_na.rm$species
bas  <- basis_pca(dat)
proj <- as.data.frame(dat %*% bas)

ggplot() +
  geom_point(aes(PC1, PC2), proj) +
  draw_basis(bas, proj, "left") +
  coord_fixed()

  
## Aesthetics and basis on specific facet levels
proj <- cbind(proj, clas = penguins_na.rm$species)
bas <- cbind(as.data.frame(bas), clas = levels(clas)[2])
ggplot() +
  facet_wrap(vars(clas)) +
  geom_point(aes(PC1, PC2, color = clas, shape = clas), proj) +
  draw_basis(bas, proj, "left") +
  theme_spinifex()

## To repeat basis in all facet levels don't cbind a facet variable.