schiek_helen

first.five <- LETTERS[seq(from= 1 , to= 5)]
last.five <- LETTERS

letters

##  [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q"
## [18] "r" "s" "t" "u" "v" "w" "x" "y" "z"

length(letters)

## [1] 26

last.five <- LETTERS[seq(from=22 , to=length(letters))]
first.five

## [1] "A" "B" "C" "D" "E"

last.five

## [1] "V" "W" "X" "Y" "Z"

every.second <- c(letters)
every.second [seq(2 , length(letters) , 2)]

##  [1] "b" "d" "f" "h" "j" "l" "n" "p" "r" "t" "v" "x" "z"

letters

##  [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q"
## [18] "r" "s" "t" "u" "v" "w" "x" "y" "z"

log.vec <- letters == "t"
log.vec

##  [1] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [12] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE
## [23] FALSE FALSE FALSE FALSE

which (log.vec )

## [1] 20

letters

##  [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q"
## [18] "r" "s" "t" "u" "v" "w" "x" "y" "z"

vowels <- c("a","e","i","o","u")
log.vec <- letters %in% vowels
log.vec

##  [1]  TRUE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE  TRUE FALSE FALSE
## [12] FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE  TRUE FALSE
## [23] FALSE FALSE FALSE FALSE

which (log.vec)

## [1]  1  5  9 15 21

seeds <- c(6, 10, 243, 12, 43, 20, 34, 18, 24, 20)
pirates <- c("Emmanuel", "Alissa", "Lucia", "Marcel", "Florian", "Nadiia", "Yvonne", "Florina", "Xu", "Zoe")

seeds > 30

##  [1] FALSE FALSE  TRUE FALSE  TRUE FALSE  TRUE FALSE FALSE FALSE

mean(seeds>30)

## [1] 0.3

log.vec <- seeds < 40
temp <- seeds[log.vec]
sd(temp)

## [1] 8.815571

log.vec <- seeds == max(seeds)
log.vec

##  [1] FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE

which(log.vec)

## [1] 3

pirates[log.vec]

## [1] "Lucia"

pirates [which(seeds == max(seeds))]

## [1] "Lucia"

pirates [which(seeds == min(seeds))]

## [1] "Emmanuel"

pirates [which(seeds > 50)]

## [1] "Lucia"

mean(seeds)

## [1] 43

sd(seeds)

## [1] 71.1368

is.outlier <- (mean(seeds)+(sd(seeds)*2))
is.outlier

## [1] 185.2736

log.vec <- seeds > (mean(seeds)+(sd(seeds)*2))
log.vec

##  [1] FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE