#A vector called v1 that contains the values 1 to 12.  
v1<-c(1:12)


#Adding the values 13 to 16 to the end of v1.
v1<-c(v1[1:12],13:16)


#A new vector v2 that contains the 1st to 7th and 12th to 16th 
#elements of v1.  
v2<-c(v1[1:7],v1[12:16])


#Adding V1+v2 - Explanation of error: once R has added the vectors together
# up to the same corresponding length, it will then recycle the shorter vector (v2) 
# starting back at the first index
v1+v2


# A new vector v3 by selecting all even elements of v1
v3<-subset(v1,v1%%2==0)


#A matrix m1 with 4 rows from vector v1.
m1<-matrix(v1,nrow=4)


#A matrix m2 with 3 columns from vector v2. 
m2<-matrix(v2,ncol=3)


#A new matrix m3 from m1 and m2 where m3 contains all of the 
#columns of both source matrices
m3<-cbind(m1,m2)


#Displays matrix m3
m3


#Labeling the columns of m3
colnames(m3)<-c("a","b","c","d","e","f","g")


#Remove row 3 from m3
m3<-m3[-3,]


#Calculate and displays means of each column.  
apply(m3,2,mean)


#A barplot of row 1 of m3.
barplot(m3[1,])