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--></style></head><body lang=EN-US link=blue vlink="#954F72"><div class=WordSection1><p class=MsoNormal>I apologize if this question has been asked before but after doing several searches I could not find an answer that is directly applicable to my problem. I am working on a package containing a number of Rcpp functions. The package builds and loads without a problem. However, when I call any of the Rcpp functions from within R, I get the following type of error message:</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Error in .Call(<pointer: (nil)>, x, xMin, xMax, adjustment) : </p><p class=MsoNormal> NULL value passed as symbol address</p><p class=MsoNormal> </p><p class=MsoNormal>As an example, here is the function that returned the error in the C++ file:</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>// [[Rcpp::export]]</p><p class=MsoNormal>NumericVector logit(Rcpp::NumericVector x, </p><p class=MsoNormal> Rcpp::NumericVector xMin,</p><p class=MsoNormal> Rcpp::NumericVector xMax, </p><p class=MsoNormal> double adjustment = 0.3) {</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal> ...</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>}</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The exported function in RcppExports.cpp:</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>// logit</p><p class=MsoNormal>NumericVector logit(Rcpp::NumericVector x, Rcpp::NumericVector xMin, Rcpp::NumericVector xMax, double adjustment);</p><p class=MsoNormal>RcppExport SEXP _MFRM_logit(SEXP xSEXP, SEXP xMinSEXP, SEXP xMaxSEXP, SEXP adjustmentSEXP) {</p><p class=MsoNormal>BEGIN_RCPP</p><p class=MsoNormal> Rcpp::RObject rcpp_result_gen;</p><p class=MsoNormal> Rcpp::RNGScope rcpp_rngScope_gen;</p><p class=MsoNormal> Rcpp::traits::input_parameter< Rcpp::NumericVector >::type x(xSEXP);</p><p class=MsoNormal> Rcpp::traits::input_parameter< Rcpp::NumericVector >::type xMin(xMinSEXP);</p><p class=MsoNormal> Rcpp::traits::input_parameter< Rcpp::NumericVector >::type xMax(xMaxSEXP);</p><p class=MsoNormal> Rcpp::traits::input_parameter< double >::type adjustment(adjustmentSEXP);</p><p class=MsoNormal> rcpp_result_gen = Rcpp::wrap(logit(x, xMin, xMax, adjustment));</p><p class=MsoNormal> return rcpp_result_gen;</p><p class=MsoNormal>END_RCPP</p><p class=MsoNormal>}</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>And the corresponding R file:</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>logit <- function(x, xMin, xMax, adjustment = 0.3) {</p><p class=MsoNormal> .Call(`_MFRM_logit`, x, xMin, xMax, adjustment)</p><p class=MsoNormal>}</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>First, how can there be two functions called "logit"--one in the main C++ file and one in RcppExports.cpp? And where does _MFRM_logit get defined? Might this be causing the problem?</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I should note that hte problem is not limited to this one function, but to all the exported C++ functions. </p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Second, is there some option in the project or in the C++ files that needs to be set? </p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I am running R 3.51, RStudio 1.14, and Rcpp (0.12.19).</p></div></body></html>