Another problem is that 'RcppDeepState_CharacterVector' uses DeepState_CStr_C and DeepState_CStrUpToLen to initialize a CharacterVector. These functions return a string. This implies that just the first character of the generated string is used in the assignments in the following code snippet.

int str_len = 20;
rand_charactervec[i] = DeepState_CStr_C(str_len, "abcdefghijklmnopqrstuvwxyz");
rand_charactervec[i] = DeepState_CStrUpToLen(str_len, "abcdefghijklmnopqrstuvwxyz");

It is preferable to construct a string of length 1 instead of generating 20 characters and taking only the first.

The RInside part was discussed in this blog post and solved in the commit 9d7413e of the pull request #6.

@tdhock if you agree with me I merge these changes into master. This pull request is meant to solve some minor bugs inside the RcppDeepState.h header file and to fix the R is already initialized error. The latter has been improved in the commit 9d7413e of the pull request #6 in order to work with seeds.

I'm not sure I understand the string issue, can you please clarify?

I got confused by the C/C++ notation where a character vector is a vector composed of single characters. However I can see that in R a character vector is composed by strings. I revert that change.

In the last commit I removed the rand_size variable inside RcppDeepState_IntegerVector(int size,int low,int high) because the size is already passed to the function, so there's no need to use a random size.

I also removed the rand_size variable in the RcppDeepState_NumericVector(int size,int low,int high) function.

in C++ Rcpp::CharacterVector ch_vec(2); has elements ch_vec[0], ch_vec[1] both of which are strings.
Each string is a null-terminated sequnce of characters.

Thank you @tdhock for the clarification.
I mistakenly believed that the syntax Rcpp::CharacterVector ch_vec(2); was equivalent to vector<char> ch_vec(2);.
The latter creates a vector of two characters, whereas the first creates two instances of Rcpp::CharacterVector, resulting in two strings.

I don't understand this naming choice of Rcpp, in fact when I write Rcpp::NumericVector v(3); I am declaring a vector of three integers.

Is it possible that the lack of a distinction between a character and a string in R is the cause of this?

clarifications:

• Rcpp::CharacterVector ch_vec(2); is analogous to std::vector<std::string> vec_of_strings; but R character vectors have a fixed size (here 2) whereas STL vectors can change in size.
• "the first creates two instances of Rcpp::CharacterVector" no, not two instances. in C++ we actually say this is a single instance of the Rcpp::CharacterVector class, which represents a vector of several strings (here 2).
• "when I write Rcpp::NumericVector v(3); I am declaring a vector of three integers." actually double precision numbers not integers.
• In R the analog for the char C type is a CharacterVector with one element. Analog for std::string C++ type is also a character vector with one element.

Thank you for the clarification, @tdhock. Now I can see the distinction. I close this pull request.