Hello I use c++ program, what call R-project to solve matrix multiplications. Some times, I get an error in R: Error in solve.default(V, R) : system is computationally singular: reciprocal condition number 2.20828e-19 Execution halted After that, the program crash. The code, what i execute, is: R.assign(arrMeans, string("R")); R.assign(arrCov, string("V")); SEXP ans; int iRet = R.parseEval("solve(V, R)", ans); Where R - vector of n size and V - matrix of n,n. Can anyone tell me, what this error means? I have check my matrix and didn't found this number. Is it because matrix too big? How can I, at last, avoid program crashing in R (it crash inside parseEval function)? WBR, Dima [[alternative HTML version deleted]]