Classification: UNCLASSIFIED Caveats: NONE New and struggling with BGL, which IMO the best for graphs. I will keep at it. This should be a simple fix for r/w Graphviz example by Douglas Gregor... The errors in the typescript (attached) are the result of "write_graphviz(std::cout,g,dp,std::string("id"));" Could someone tell me how/what to correct. Thank you. Classification: UNCLASSIFIED Caveats: NONE