cerr<<"ERROR: evaluation of Jacobian failed for equation "<<eq+1<<" (line "<<equations_lineno[eq]<<") and variable "<<symbol_table.getName(symb)<<"("<<lag<<") ["<<symb<<"] !"<<endl;
cerr<<"ERROR: evaluation of Jacobian failed for equation "<<eq+1<<" (line "<<equations_lineno[eq]<<") and variable "<<symbol_table.getName(symb)<<"("<<lag<<") ["<<symb<<"] !"<<endl;