kmeans

Is there any way that I can assure that kmeans always returns the same
result for the same data by locking down the random number generator
or anything else?

David

Try ?set.seed before your call to kmeans:

# from ?kmeans
# a 2-dimensional example
x <- rbind(matrix(rnorm(100, sd = 0.3), ncol = 2),
            matrix(rnorm(100, mean = 1, sd = 0.3), ncol = 2))
colnames(x) <- c("x", "y")

# set seed for random number generator
set.seed(42)
cl.1 <- kmeans(x, 5, nstart = 25)
set.seed(42)
cl.2 <- kmeans(x, 5, nstart = 25)

# check whether objects are identical
all.equal(cl.1, cl.2)

HTH,
--sundar

Is there any way that I can assure that kmeans always returns the same
result for the same data by locking down the random number generator
or anything else?

?set.seed

David

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