number8<-5+3 #sums 5 and 3 and ssaves the result into object number8

getwd()#displays working directory

?boxplot # displays help for the function boxplot


vec.1<-c(1, 2,5,4,8,10.8)# Creates vector containing 
vec.1[5] #Displays the 5th value of vec.1

install.packages("readxl")# installs the package readxl
library(readxl)# loads the package readxl


people<-read_excel("people.xlsx")# imports the people dataset from csv file into people dataframe

people<-read.delim2("clipboard") # imports the people dataset from clipboard into people dataframe

summary(people)#diplays summary of the people dataframe
class(people)# shows object type of people
# [1] "data.frame"
class(people$eye.color)
# [1] "character"
class(people$height)
# [1] "numeric"

quantile(people$height)# computes quantiles of height values
#    0%   25%   50%   75%  100% 
# 160.0 174.5 180.0 185.0 200.0 

people[1:3,]# selectes and displays first three rows of the people dataframe

males<-people[people$sex=="M",]# Create a new dataframe containing just data on males

aggregate(people$height, list(people$sex), median)#computes aggregated meadian height values for males and females
tapply(people$height, list(people$sex), median)# the same with different output format

hist(people$height)#Plots histogram of heights

boxplot(height~sex, data=people)#Plots a boxplot showing association between sex and heights