Better estimated luck with less numerical error

src/rpc.cpp

@@ -928,12 +928,14 @@ void RPC::getInfoThenRefresh(bool force) {
                     luck->display( QString("-") );
                 } else {
                     // luck = current estimate of time to find a block given current localhash and nethash
-                    double percentOfNetHash = localhashps.toDouble() / networkhashps.toInt();
+                    //TODO: maybe use this as a tooltip
+                    double percentOfNetHash = localhashps.toDouble() / networkhashps.toDouble();
                     DEBUG( "% of nethash=" << percentOfNetHash );
-                    if (percentOfNetHash > 0) {
+
+                    if (localhashps.toDouble() > 0) {
                         //TODO: this is only for DRAGONX
                         int blocktime = 36;
-                        double luckInSeconds = (1/percentOfNetHash)*blocktime;
+                        double luckInSeconds = (networkhashps.toDouble()/localhashps.toDouble())*blocktime;
                         double luckInHours   = luckInSeconds / (60*60);
                         luck->display( QString::number( luckInHours , 'f', 2 )  );
                     }