One error message you may encounter when using R is:
Error in 5 <- read.table("data.txt") :
invalid (do_set) left-hand side to assignment
This error occurs when you attempt to create a variable in R that starts with a number.
By default, R only allows you to define variable names that start with either a character or a dot.
The following example shows how to resolve this error in practice.
How to Reproduce the Error
Suppose I attempt to use the read.table() function to read a file into R:
#attempt to read text file into R
5 <- read.table("data.txt")
Error in 5 <- read.table("data.txt") :
invalid (do_set) left-hand side to assignment
I receive an error because I attempted to create a variable name that started with a number.
How to Avoid the Error
To avoid the error, I must use a variable name that starts with a character or a dot.
For example, I could use the following variable name that starts with a character:
#read text file into R
data5 <- read.table("data.txt")
#view contents of text file
data5
V1 V2
1 1 4
2 3 4
3 2 5
4 7 9
5 9 1
6 6 3
7 4 4
Or I could even use the following variable name that starts with a dot:
#read text file into R
.data5 <- read.table("data.txt")
#view contents of text file
.data5
V1 V2
1 1 4
2 3 4
3 2 5
4 7 9
5 9 1
6 6 3
7 4 4
Once again I don’t receive an error because I didn’t start the variable name with a character.
Note that you can type the following into R to read the complete documentation on how to create syntactically valid names:
?make.names
Additional Resources
The following tutorials explain how to fix other common errors in R:
How to Fix in R: Arguments imply differing number of rows
How to Fix in R: error in select unused arguments
How to Fix in R: replacement has length zero
