Hi, I am using BOOST to do math and have not been able to get the "findroot_demo.cpp" example of root finding to work. There seem to be a reference to rint(), which is not implemented in the C++ library for windows. How can I solve this - my understanding of BOOST is that it is cross-platform? 1>------ Build started: Project: boostfindzero, Configuration: Debug Win32 ------ 1>Compiling... 1>findroot_demo.cpp 1>Linking... 1>findroot_demo.obj : error LNK2019: unresolved external symbol _rint referenced in function "public: static double __cdecl boost::numeric::interval_lib::detail::x86_rounding::to_int(double const &)" (?to_int@x86_rounding@detail@interval_lib@numeric@boost@@SANABN@Z) 1>D:\dokumenter\lvm_AM\Visual Studio 2008\Projects\boostfindzero\Debug\boostfindzero.exe : fatal error LNK1120: 1 unresolved externals 1>Build log was saved at "file://d:\dokumenter\lvm_AM\Visual Studio 2008\Projects\boostfindzero\boostfindzero\Debug\BuildLog.htm" 1>boostfindzero - 2 error(s), 0 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== Thanks in advance. /Lars