PhysicalActivityandStrokeOu.../1 PA Decline/PCA.R
2022-09-28 16:03:58 +02:00

75 lines
2.1 KiB
R

## ItMLiHSmar2022
## PCA.R, child script
## Principal components analysis for data visualisation
## Andreas Gammelgaard Damsbo, agdamsbo@clin.au.dk
## ====================================================================
## Step 0: data wrangling
## ====================================================================
# source("data_format.R")
X1<-X %>% dplyr::mutate(across(where(is.factor), as.numeric))
pc.out<-prcomp(X1, center=TRUE, scale = TRUE)
pc.sum<-summary(pc.out)
## ====================================================================
## Step 1: plotting
## ====================================================================
Xy$group<-factor(Xy$group,labels = c("No decline", "Decline"))
library(ggfortify)
ppc12 <- autoplot(pc.out,
data = Xy,
x=1,
y=2,
colour = 'group')+
labs(title = "PC1 and PC2",
colour = "Outcome")
ppc13 <- autoplot(pc.out,
data = Xy,
x=1,
y=3,
colour = 'group')+
labs(title = "PC1 and PC3",
colour = "Outcome")
ppc23 <- autoplot(pc.out,
data = Xy,
x=2,
y=3,
colour = 'group')+
labs(title = "PC2 and PC3",
colour = "Outcome")
# Scree plot
pscr<-tibble(x=1:dim(pc.sum$importance)[2],
Proportion=pc.sum$importance[2,],
Cumulative=pc.sum$importance[3,])%>%
pivot_longer(cols=-x)%>%
ggplot(aes(x=x,y=value,color=name))+
geom_line()+
geom_point()+
ylim(0,1)+
labs(title = "Scree plot",
color= "Variance")+
ylab("Variance")+
xlab("Principal components")
## ====================================================================
## Step 2: merge plots
## ====================================================================
library(patchwork)
pca22<-ppc12+
theme(legend.position="none")+
ppc13+
ppc23+theme(legend.position="none")+
pscr+
plot_layout(ncol=2)+
plot_annotation(title = 'Principal component visualisation',
tag_levels = "A")
# pca22