# NOT RUN {
library(nipals)
data(uscrime)
# SAS deletes rows with missing values
dat <- uscrime[complete.cases(uscrime), ]
dat <- as.matrix(dat[ , -1])
m1 <- nipals(dat) # complete-data method
# Traditional NIPALS with missing data
dat <- uscrime
dat <- as.matrix(dat[ , -1])
m2 <- nipals(dat, gramschmidt=FALSE) # missing
round(crossprod(m2$loadings),3) # Prin Comps not quite orthogonal
# Gram-Schmidt corrected NIPALS
m3 <- nipals(dat, gramschmidt=TRUE) # TRUE is default
round(crossprod(m3$loadings),3) # Prin Comps are orthogonal
# }
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