RServeCLI - Issue : RserveCLI2.RserveException

Question

I need some help on what may be a simple issue. I am trying to access R using a simple .Net /C# Console application.

I have installed the program R on a virtual Server which use Ubuntu 14.04 LTS as it's OS. I have also installed the package Rserve as well. With Rserve and a client library called RserveCLI, source code. I am now able to connect to the to the instance or R running on the virtual server.

Now here comes the problem, I can make the connection, but when i try to perform the example used in the source code with in my own solution. I am getting the following error:

"RserveCLI2.RserveException: Cannot decode an Sexp because the type is not recognized: 48"

            //Setting up the connection and sending information trhough connection to                 be processed
            using ( var s = new RConnection( new System.Net.IPAddress( new byte[] { 192 , 168 , 201 , 101 } ) , port: 6311 , user: NULL , password: NULL ) )
            {
                    // Generate some example data
                    var x = Enumerable.Range( 1 , 20 ).ToArray();
                    var y = ( from a in x select ( 0.5 * a * a ) + 2 ).ToArray();

                    // Build an R data frame
                    var d = Sexp.MakeDataFrame();
                    d[ "x" ] = Sexp.Make( x );
                    d[ "y" ] = Sexp.Make( y );
                    s[ "d" ] = d;

                    // Run a linear regression, obtain the summary, and print the result
                    var linearModelSummary = s[ "summary(lm(y ~ x, d))" ];
                    Console.WriteLine( linearModelSummary.Count );
            }

The error comes from it tries to process: var linearModelSummary = s[ "summary(lm(y ~ x, d))" ];

The issue is with the variable d. When I look at the serve with current instance I have opened with Rserve. It says "Error: object 'd' not found"

Tools And Software Used:

Visual Studio 2013,.Net Framework 4.5, R, Rserve Version=1.7-3, RServeCLI, Virtual Box Version = 4.3.10, OS on Laptop = Win 7 64 Bit, OS on Virtual Server = Ubuntu Server LTS 14.04

Any advice would be helpful as I am not sure what I am doing wrong. If you need any more information, please ask I will try and get it for you.

Thanks

Answer 1

Do not try to use RServeCLI in that way, you will never get it to work reliably. Instead, put all code into a function in R, test it separately, and only pass values and data frames between R and c#.

In your case the problem is in the summary line, because this structure cannot be marshalled with the available tools. Transfer the results to a simple list or better, as a starter, to atomic variables.

Answer 2

Thanks Dieter for the advice. Tried using the built in function getwd(), and performing basic arithmetic stuff. All working fine so far. Cheers