Tutorial # 5. Data Frame

Data Frames : It is a frame of data stored in a two dimensional array which contains row & column
each row pointing a set of value of corresponding column.

# Syntax :  data.frame ( vector1 , vector2 , ...... )

 

Example:

city = c("Delhi" , "Mumbai" , "Chennai" , "Kolkata")

area = c("40 sqKm" , "35 sqKm" , "45 sqKm" , "55 sqKm")

population = c(4500000 , 5000000 , 3500000 , 2800000)

df = data.frame(city , area , population)

print(df)

 

Output: 

city area population
1 Delhi 40 sqKm 4500000
2 Mumbai 35 sqKm 5000000
3 Chennai 45 sqKm 3500000
4 Kolkata 55 sqKm 2800000

Accessing the Data Frame  

Example: 

print(df$city)

print(df$population)

print(df[1])

print(df[ , 1])

print(df[ 1 , ])

print(df['city'])

Manipulating the Data Frame   

Example:  

df$population = df$population*100

print((df))

 

# provides summary of the data frame 

print(summary(df))

 

Output: 

  

 

  city area population
1 Delhi 40 sqKm 4.5e+08
2 Mumbai 35 sqKm 5.0e+08
3 Chennai 45 sqKm 3.5e+08
4 Kolkata 55 sqKm 2.8e+08

city area population
Chennai:1 35 sqKm:1 Min. :280000000
Delhi :1 40 sqKm:1 1st Qu.:332500000
Kolkata:1 45 sqKm:1 Median :400000000
Mumbai :1 55 sqKm:1 Mean :395000000
3rd Qu.:462500000
Max. :500000000 

 

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An Introduction to language R

Tutorial # 1.Data Type & Variable  Declaration
Tutorial # 2.Operators
Tutorial # 3.Vector  & Element Access
Tutorial # 4.Matrix
Tutorial # 5.Data Frame

Tutorial # 6.Arrays
Tutorial # 7.Lists
Tutorial # 8.Factors
Tutorial # 9.Data import
Tutorial # 10.Machine Learning
Tutorial # 11.Visualization