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NOTE: THIS IS R PROGRAMMING: Discuss how to solve the following problems use R c

ID: 3773785 • Letter: N

Question

NOTE: THIS IS R PROGRAMMING: Discuss how to solve the following problems use R code. You’re not just writing the R code, you are also discussing the process.

Considering the following data frame called items (note the row names and column names):

store id

item name

price

entry 1

1

milk

$1.99

entry 2

2

egg

$0.99

entry 3

3

fish

$1.99

entry 4

4

pork

$3.99

entry 5

5

beef

$4.99

Write R code(s) to:

retrieve all the information for entry2;

Retrieve all the item names;

Use two ways to retrieve beef;

Retrieve the item name and price columns for store id greater than 3.

The resulting data frame for (d) should look like below.

item name

price

entry 4

pork

$3.99

entry 5

beef

$4.99




Considering this function header:
myFun=function(first=10,second=20,third=30,fourth=40), List the values of first,
second, third, and fourth when we call myFun in the following ways.

myFun()

myFun(second=60,70)

myFun(fourth=10,first=20,50,80)

store id

item name

price

entry 1

1

milk

$1.99

entry 2

2

egg

$0.99

entry 3

3

fish

$1.99

entry 4

4

pork

$3.99

entry 5

5

beef

$4.99

Explanation / Answer

item <- data.frame(
       store_id = c(1:5),
       item_name = c("milk","egg","fish","pork","beef"),
       price = c(1.99,0.99,1.99,3.99,4.99),
       stringsAsFactors=FALSE
   )

# retrieve all the information for entry2;
result <- emp.data[2]
print (result)


# Retrieve all the item names;

result <- data.frame(item$item_name)
print(result)


# Use two ways to retrieve beef;

# 1st way
item

# 2nd way
result <- data.frame(item$store_id,item$item_name,item$price)
print(result)


# Retrieve the item name and price columns for store id greater than 3

result <- data.frame(ifelse(item$store_id > 3, (item$item_name,item$price), NA))
print result