04pallav
9/13/2017 - 9:26 PM

Principal Components Analysis

Principal Components Analysis

pr.out =prcomp (nci.data , scale=TRUE)

Cols=function (vec ){
cols=rainbow (length (unique (vec )))
return (cols[as.numeric (as.factor (vec))])
}

par(mfrow =c(1,2))
plot(pr.out$x [,1:2], col =Cols(nci .labs), pch =19,
xlab ="Z1",ylab="Z2")
plot(pr.out$x[,c(1,3) ], col =Cols(nci.labs), pch =19,
xlab ="Z1",ylab="Z3")

summary (pr.out)

plot(pr.out)

##SCREE PLOT
pve =100* pr.out$sdev ^2/ sum(pr.out$sdev ^2)
par(mfrow =c(1,2))
plot(pve , type ="o", ylab="PVE ", xlab=" Principal Component ",col =" blue")
plot(cumsum (pve ), type="o", ylab =" Cumulative PVE", xlab="Principal Component ", col =" brown3 ")