Extract first N rows from dataframe in R

Extract vector from dataframe in R

Last Updated : 07 Apr, 2021

In this article, we will see how to extract vectors from DataFrame in R Programming Language.

The approach is simple, by using $ operator, we can convert dataframe column to a vector.

Syntax:

dataframe_name$columnname

Given below are various examples to implement the same

Example 1:

R

# create vector with names
name=c("sravan","mohan","sudheer","radha","vani","mohan")

# create vector with subjects
subjects=c(".net","Python","java","dbms","os","dbms")

# create a vector with marks
marks=c(98,97,89,90,87,90)

# create vector with height
height=c(5.97,6.11,5.89,5.45,5.78,6.0)

# create vector with weight
weight=c(67,65,78,65,81,76)

# pass these vectors to the data frame
data=data.frame(name,subjects,marks,height,weight)

# display dataframe
print(data)

# access vector from dataframe column name
a=(data$name)
print(a)

# access vector from dataframe column marks
b=(data$marks)
print(b)

Output:

Example 2:

R

# create vector with height
height=c(5.97,6.11,5.89,5.45,5.78,6.0)

# create vector with weight
weight=c(67,65,78,65,81,76)

# pass these vectors to the data frame
data=data.frame(height,weight)

# display dataframe
print(data)

# access vector from dataframe column
# weight
a=(data$weight)
print(a)

# access vector from dataframe column 
# height
b=(data$height)
print(b)

Output:

Extract first N rows from dataframe in R

P

pulamolusaimohan

Improve

Article Tags :

Similar Reads

Extract first N rows from dataframe in R

A required number of rows can be retrieved from a dataframe for some computation that demands so. In this article, we will be discussing two different approaches for extracting the first n rows from the data frame File in Use: Method 1: Using head() function This function will help to extract the gi

Extract rows from R DataFrame based on factors

In this article, we will discuss how to extract rows from dataframe based on factors in R Programming Language. Method 1: Using indexing methods The data frame column can be accessed using its name (df$col-name) or by its index (df[[ col-indx ]]) to access a particular column. The data frame columns

Extract Numbers from Character String Vector in R

In this article, we are going to see how to extract Numbers from Character String Vector in R Programming Language. There are different approaches to extract numbers from character string vectors using some in-built functions. It can be done in the following ways: Using the gsub() functionUsing the

How to Extract a Column from R DataFrame to a List ?

In this article, we will discuss how to extract a column from a DataFrame to a List in R Programming Language. Method 1: Converting all columns to list In this method, we are going to create a vector with character (names) and integer(marks) type data and passing to the student dataframe. Similarly,

How to extract column from data frame as vector in R ?

In this article, we are going to convert dataframe column into a vector in R Programming Language. Steps -Create vectorsCreate a dataframe by passing these vectorsConvert dataframe column using"[[]]" operator (indexing). [[]] is used to access the dataframe column.It is used to index the dataframe.

Reshape DataFrame from Long to Wide Format in R

In this article, we will discuss how to reshape dataframe from long to wide format in R programming language. The data in the dataframe is recognized by the format in which the storage and retrieval happens. Duplicate key-value pairs exist in dataframe and can be rearranged using the following metho

How to Delete Row(s) in R DataFrame ?

In this article, we will see how row(s) can be deleted from a Dataframe in R Programming Language. Deleting a single row For this, the index of the row to be deleted is passed with a minus sign. Syntax: df[-(index), ] Example 1 :Â [GFGTABS] R # creating a data frame with # some data . df=data.frame(

How to add Header to Dataframe in R ?

A header necessarily stores the names or headings for each of the columns. It basically helps the user to identify the role of the respective column in the data frame. The top row containing column names is called the header row of the data frame. In this article, we will learn how to add a Header t

How to add dataframe to dataframe in R ?

In this article, we will see how to add dataframe at the end of another dataframe in R Programming Language. Method 1: Using rbind() method The rbind() method in R works only if both the input dataframe contains the same columns with similar lengths and names. The dataframes may have a different num

Extract given rows and columns from a given dataframe in R

Extraction of given rows and columns has always been one of the most important tasks which are especially required while working on data cleaning activities. In this article, we will be discussing all the sets of commands which are used to extract given rows and columns from a given dataframe in the