Insert multiple rows in R DataFrame
In this article, we are going to see how to insert multiple rows in the dataframe in R Programming Language. First, let’s create a DataFrame
To create a data frame we need to use vectors. We need to create vectors with some values and pass the vectors into data.frame() function as parameter. Thus, a data frame is created. Let us see an example that demonstrates the above statement.
Example 1:
R
# here num and branches are the vectors, ans those # are passed into data.frame() as parameters . dataframe = data.frame (num= c (1:3),branches= c ( "IT" , "CSE" , "ECE" )) # In this example we created vectors inside the # data frame() function and assigned values to vectors. print (dataframe) |
Output:
In the above example, we have created a data frame with vectors directly as parameters. We can create data frames with already created vectors. Let us see an example.
Steps to insert multiple rows into a data frame
- Create a dataframe.
- Create a vector that contains rows to be added to the dataframe.
- Use the below method to add rows to the data frame.
Implementation :
The predefined function used to add multiple rows is rbind(). We have to pass a data frame and a vector having rows of data. So, let see the example code.
Indexing for a dataframe in R:
variable = df([ row,column ])
If we want to extract multiple rows we can put row numbers in a vector and pass that vector as a row or column. If we want to extract 3 rows and all columns we can put row numbers in a vector and leave the column empty. The below example demonstrates the above statement.
Example :
a = df1([ c(1,2,3) , ]) # here we left column as empty which means we want extract all columns
If we want to extract specific columns then we can put column numbers in a vector and pass as a parameter. The below example demonstrates the above statement.
Example :
b = df1( [ c(1,2,3) , c(1,2) ] )
This is how indexing works. Let us see rbind() function introduction and implementation for inserting multiple rows into a dataframe.
rbind() method: rbind means row bind. Joining multiple rows with dataframe.
Syntax: rbind(a, b)
Parameters:
- a = data frame
- b = data to be binded with data frame
Example 1 :
R
# creating a data frame df1 = data.frame (num = c ( 1 : 3), branch = c ( "IT" , "CSE" , "ECE" )) # creating another data frame df2 = data.frame (num = c ( 4 : 6), branch = c ( "EEE" , "Mechanical" , "civil" )) # selecting 1-2 rows , all columns from df1 new_row = df2[ c (1, 2, 3),] # we can access data from a data frame through indexing . # since it is a 2 dimensional one we can access data # by row number and column number . # here c(1,2,3) represents row numbers and we left column # numbers as empty . then all columns are accessed . # new_row is appended to the df1 df1 = rbind (df1, new_row) #printing updated data frame print (df1) |
Output:
Example 2: Adding rows from 3 dataframe.
R
# creating one data frame df1 = data.frame (num = c ( 1 : 3 ), branch = c ( "IT" , "CSE" , "ECE" )) # creating another data frame df2= data.frame (num = c ( 4 : 6 ), branch = c ( "Chemical" , "Petroleum" , "Food Technology" )) df3= data.frame (num = c ( 7 : 9 ), branch = c ( "EEE" , "Mechanical" , "Civil" )) # here we accessing 1-3 rows and all columns # from df2 and storing in new_row variable new_row=df2[ c (1, 2, 3),] # here also we are accessing 1-3 rows and all # columns and storing in new_row2 variable new_row2=df3[ c (1, 2, 3),] # passing data frame1 i.e., df1 and the new_row . df1= rbind (df1, new_row) # passing data frame1 i.e., df1 and new_row2 df1= rbind (df1, new_row2) # Here values in new_row will be appended with df1 . # if we pass df2,new_row , # the data in the nw_row will be appended with df2 print (df1) # printing df1 |
Output: