Qaudiooutput Double values

[Sareban]

Hi. I am a newbie to qt and c++. I am writing a simple signal generator right now. ı am tryimg to create a qbytearray from doubles but qbytearray changes all of the doubles to integer. So i lose precision on the sound waves. How can i make qbytearray store double or float variables?
My code is like this which generates a simple sinewave
@
int len= m_seconds*SAMPLE_RATE;

sinbuf.resize(len);

for(int i=0;i<len;i++){
    qreal t = m_freq*i;
    t *= FREQ_CONST;
    t = t+ m_ph;
    t = qSin(t);
    t*= m_amp;

    sinbuf[i] = t;
}

sininput.setBuffer(&sinbuf);
sininput.open(QIODevice::ReadWrite);

@

It just invludes integers from -100 to 100. I need it to include floats or doubles. I tried populating a qvector and stream it to the array via qdatastream but it just made every element put randomly and also integers.
Thamks for your help