Was just in your UseR tutorial and you said to add an issue. I had 2 problems with a Windows computer R3.1.

1. When I had an error in the cpp file, I didn't get a compile error and instead just got a message that the dll could not be loaded. When I set verbose=TRUE then I could see the error.
2. If I edited the cpp file and redid sourceCpp() it did not use the new version of the code. I had to either restart R or rename the exported function.

Thanks for a great tutorial. --jeff (the guy in the back in the Hawaiian shirt)