Hi,

Im currently making a calculator in c++.net 2003.

I've got it to 'square' numbers and produce a result. Heres the code:-

void CAssignmentDlg::OnBnClickedButton21()
{
    m_fSquare=m_fSquare+atof(m_sDisplay);
    m_sDisplay="";
    m_fSquareRes = m_fSquare * m_fSquare;
    char strSquare[20];
    m_fmem=m_fSquareRes;
    gcvt(m_fmem,6,strSquare);
    for (int i = 0;i<20;i++)
    m_sDisplay = m_sDisplay+strSquare[i];

    UpdateData(FALSE);
}

My problem is how to make another button produce the square rrot of a number, it is essentially the inverse of this code but i really dont know how to do it!

Could someone give me a hand?
Thanks
Ash:D

My new web design domain
www.askmultimedia.co.uk

__________________
My new web design domain
www.askmultimedia.co.uk

Use the sqrt() function (prototyped in math.h) to find the square root.

Regards,

Dave

Thanks for the help, that works, would i use the same method to use other mathmatical functions?

For example sin() would be

m_fSin=m_fSin+atof(m_sDisplay);
    m_sDisplay="";
    m_fSinRes = sin(m_fSin);
    char strSin[20];
    m_fmem=m_fSinRes;
    gcvt(m_fmem,6,strSin);
    for (int i = 0;i<20;i++)
    m_sDisplay = m_sDisplay+strSin[i];

    UpdateData(FALSE);

Ive just tried that and it compiles, but gives me a strange result when testing, i type 45 then sin() and the answer should be 0.707, yet i get 0.850904???????

Is this anything to do with the fact its a floating point number? 'just a guess by the way!'

Thanks
Ash

My new web design domain
www.askmultimedia.co.uk

sin, cos, tan, etc all use radians as arguments and the sin of 45 radians is .859035247...

These are double precision functions, and give about 16 correct significant decimal digits. So floating point roundoff for these functions would not result in an error as large as you guessed.

Regards,

Dave