Question

Using the R language:

Suppose we have a vector, called longvector with 1000 elements. A. How would you let R calculate the mean value of longvector? Write the code here:

B. What if there are some NA values and you'd like R to remove the NA values when calculating the mean of longvector? Write the code here:

C. How would you plot a histogram to show the distribution of values in longvector? Write the code here:

D. How would you sample a random element from longvector? Write the code here:

Answer 1

Solution: A) #Declare vect r longvector <1:1000; #calculate mean mean (longvector) Output: 4.3s Rscript main.r [1] 500.5 B) #Declare vect r longvector < 11000; #Last value made as NA longvector[1000] NA #Calculate mean me an (1 ngvect r , na . rm=TRUE) Output: 3 4.3 Rscript main.r [1] 500 C) #Declare vect r with random values longvector <- runif (n-1000,min-1,max-100) #hist gram of longvector hist (longvector) Output:

Histogram of longvector 20 40 60 80 100 longvector D) #Declare vector with random values longvector <- runif (n-1000,min-1,max-100) #sample a random element sample (longvector,1) Output: > longvector <- runif (n-1000,min-1,max-100]) > sample (longvector, 1) [11 97.22485

Code:

A)

#Declare vector

longvector <- 1:1000;

#calculate mean

mean(longvector)

B)

#Declare vector

longvector <- 1:1000;

#Last value made as NA

longvector[1000]=NA

#Calculate mean

mean(longvector,na.rm=TRUE)

C)

#Declare vector with random values

longvector <- runif(n=1000,min=1,max=100)

#histogram of longvector

hist(longvector)

#Declare vector with random values

longvector <- runif(n=1000,min=1,max=100)

#sample a random element

sample(longvector,1)