How To Fix the Error in readchar(con, 5l, usebytes = true) : cannot open the connection

When working in R studio you will get the “cannot open the connection” error message if you try to read a data file that is not there. This can occur because you have the wrong filename, because the data file is someplace else, or simply does not exist on your system. Fixing it requires, making sure that the data file exists where it is supposed to, and that you are calling the correct filename.

Description of the error

The “cannot open the connection” error message occurs when you are trying to read a data file that your program cannot find. This can occur because the file is part of a package that you have not installed or that it is from a different r version. It can occur because you have miss-typed the filename, file extension, or some part of its path. You could have received it in a previous message from someone, but never actually downloaded it. Fixing the problem is a matter of making sure that the file has the correct name and is where your program is looking for it. Once you have loaded the data file you will get all the variables it contains, and you can apply analytical tools like the plot function to it.

Explanation of the Error

Here is an example of some r code that causes the “cannot open the connection” error message.

> df1 = data.frame(z = c(“A”, “B”, “C”, “D”, “E”),
+ x = c(1, 2, 3, 4, 5),
+ y = c(2, 3, 4, 5, 6))
>
> df2 = data.frame(x = c(1, 2, 3, 4, 5, 6, 7, 8),
+ y = c(2, 3, 4, 5, 6, 7, 8, 9))
>
> df3 = data.frame(X = c(“A”, “B”, “C”, “D”, “A”, “D”),
+ Y = c(111, 211, 311, 411, 122, 444))
>
> save(list = c(“df1”, “df2”, “df3”), file = “test1.rda” )
>
> load(“test.rda”)
Error in readChar(con, 5L, useBytes = TRUE) : cannot open the connection
In addition: Warning message:
In readChar(con, 5L, useBytes = TRUE) :
cannot open compressed file ‘test.rda’, probable reason ‘No such file or directory’

In this example, we first create a data file, so there is a data file to load if the code is entered properly. If you look at the load function, you will notice that the filename is not spelled correctly. As a result, the program cannot find the file and it returns our error message.

How To Fix the Error

Here is an example, of some code that fixes the “cannot open the connection” error message.

> df1 = data.frame(z = c(“A”, “B”, “C”, “D”, “E”),
+ x = c(1, 2, 3, 4, 5),
+ y = c(2, 3, 4, 5, 6))
>
> df2 = data.frame(x = c(1, 2, 3, 4, 5, 6, 7, 8),
+ y = c(2, 3, 4, 5, 6, 7, 8, 9))
>
> df3 = data.frame(X = c(“A”, “B”, “C”, “D”, “A”, “D”),
+ Y = c(111, 211, 311, 411, 122, 444))
>
> save(list = c(“df1”, “df2”, “df3”), file = “test1.rda” )
>
> load(“test1.rda”)

In this example, we fixed the problem by correcting the filename from “test.rda” to “test1.rda.” This solves the problem because now it can load in the variables since “test1.rda” is right where we put it. If the files you are trying to load are part of a package, then the way to fix the problem is to install the package. If the files are not in the correct directory, then either move them or supply a path to the proper directory. All these methods fix the problem, but it does make solving this problem a little harder.

The “cannot open the connection” error message can occur for several different reasons; this makes fixing it a little tricky. However, it is an easy problem to understand, and once you understand what causes it fixing it is easy. They can include, installing a package, moving files around, and correcting the filename you gave the load function. The challenge is finding the cause for a given instance of this problem. However, from there correcting the problem is simple.

Scroll to top