that is wrong way of doing it

try this:

QByteArray bytesArray QDataStream out(&bytesArray ,QIODevice::WriteOnly); out << someVector; //saves it //////////////////////////////////////////////////////////////////// QDataStream in(bytesArray); QVector<qreal> otherVector; in >> otherVector; //load

Please note that qreal is only 99.9% safe when saving to stream and sending it around to programs built with other versions of Qt. use QVector<double> instead