The methods you are trying to use are obsolete and have been removed. R.NET 1.5.5 is superseded by newer versions hosted at https://www.nuget.org/packages/R.NET.Community
Follow the documentation at https://rdotnet.codeplex.com/documentation, which will refer to new NuGet locations and the current API.
See also previous discussions WRT R.NET versions, for instance https://rdotnet.codeplex.com/discussions/561524
Follow the documentation at https://rdotnet.codeplex.com/documentation, which will refer to new NuGet locations and the current API.
See also previous discussions WRT R.NET versions, for instance https://rdotnet.codeplex.com/discussions/561524