RinAction - R Functions - Useful Functions

gistfile1.r

###########################################
##           Other Useful Functions      ##
###########################################

# remove a self-written function from memory
rm('knn')

# length of object
x <- length(c(2,5,6,7))
x

# generate a sequence
indices <- seq(1,10,2)
indices

# Repeat 
y <- rep(1:3, 2)
y

# Divide continuous variabl x into factor with n levels

# Create pretty breakpoints
# Divide a continous variable x into n intervals, by selecting
# n+1 equality spaced rounded value. Often used in plotting

#concatenate the objects and outputs them to the screen or a file
firstname <- c("Jane")
cat("Hello", firstname, "\n")

# Random sampling using sample() function

set.seed(1) # use the same seed to regenerate same permutation
x <- 1:100
sample(x) # random permutation
sample(x,50) # select 50 random sample
sample(x,50,replace=TRUE) # sampling with replacement