Principal Component Analysis in R data color

r ggbiplot
Natalia Crisóstomo picture Natalia Crisóstomo · Oct 7, 2012 · Viewed 12.4k times · Source

Hi everyone I have a simple question but for which i havent been able to get an answer in any tutorial. Ive done a simple principal component analysis on a set of data and then plot my data with biplot. 

CP <- prcomp(dat, scale. = T)
summary(CP)

biplot(CP)

With this i get a scatter plot of my data in terms of the first and second component. I wish to separate my data by color, indicating R to paint my first 20 data in red and next 20 data in blue. I dont know how to tell R to color those two sets of data. Any help will be very appreciated. thks! (im very new to R)

Answer

MYaseen208 picture MYaseen208 · Oct 7, 2012

Disclaimer: This is not a direct answer but can be tweak to obtain the desired output.

library(ggbiplot)
data(wine)
wine.pca <- prcomp(wine, scale. = TRUE)
print(ggbiplot(wine.pca, obs.scale = 1, var.scale = 1, groups = wine.class, ellipse = TRUE, circle = TRUE))

enter image description here

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