How to Fix: names do not match previous names in R

In this article, we are going to solve the error “names do not match previous names” in R Programming Language.

Generally, this error is produced due to the columns name not matching while combing several vectors, dataframe.

How to produce the error?

Here we have created two dataframe with 4 different column names(num, course, Marks, Subject) while using rbind() will occur the error.

R

# Create data for chart
val1 <-data.frame("num"=c(77,55,80,60),
                 "course"=c('DSA','C++','R','Python'))
print(val1)

val2 <-data.frame("Marks"=c(23,45,81,80),
                 "Subject"=c('COA','OS','SE','AI'))
print(val2)
rbind(val1,val2)

Output:

  num course
1  77    DSA
2  55    C++
3  80      R
4  60 Python
  Marks Subject
1    23     COA
2    45      OS
3    81      SE
4    80      AI

Error in match.names(clabs, names(xi)): names do not match previous names

How to solve this error

Method 1: Changes columns name

To solve this error we have to change the columns name, for this, we will create the third dataframe and copy the second dataframe into it, and copy the columns from the first dataframe as shown in the below code.

R

# Create data for chart
val1 <-data.frame("num"=c(77,55,80,60),
                 "course"=c('DSA','C++','R','Python'))

val2 <-data.frame("Marks"=c(23,45,81,80),
                 "Subject"=c('COA','OS','SE','AI'))
# Replicate data
val3 <- val2

# Change column names
colnames(val3) <- colnames(val1)
rbind(val1,val3)

Output:

num    course
77    DSA
55    C++
80    R
60    Python
23    COA
45    OS
81    SE
80    AI

Method 2:  Rename Columns name

We can rename the columns name to solve this error, for this we will copy the columns into 2nd dataframe.

R

# Create data for chart
val1 <-data.frame("num"=c(77,55,80,60),
                 "course"=c('DSA','C++','R','Python'))

val2 <-data.frame("Marks"=c(23,45,81,80),
                 "Subject"=c('COA','OS','SE','AI'))

# rename second data frame columns
names(val2) <- names(val1)

# row bind the two data frames
rbind(val1, val2)

Output:

77    DSA
55    C++
80    R
60    Python
23    COA
45    OS
81    SE
80    AI

Method 3: Using dplyr package

Here we will use bind_rows() methods from the dplyr package, it will create each column along with the existing value if the dataframe has no element into it then it saves as NA elements. 

R

library("dplyr")

# Create data for chart
val1 <-data.frame("num"=c(77,55,80,60),
                 "course"=c('DSA','C++','R','Python'))

val2 <-data.frame("Marks"=c(23,45,81,80),
                 "Subject"=c('COA','OS','SE','AI'))

bind_rows(val1, val2)

Output:

num    course    Marks    Subject
77    DSA    NA    NA
55    C++    NA    NA
80    R    NA    NA
60    Python    NA    NA
NA    NA    23    COA
NA    NA    45    OS
NA    NA    81    SE
NA    NA    80    AI