VB.net problem

[Aastii]

I am making a calculator in VB 2008 and trying to put in trig functions.

Now I know that when you do any trig function in VB it comes out in radians rather than degrees, and to convert from radians to degrees you must *Pi/180, however whenever I do it, it comes out wrong.

My code is:

Private Sub cmdSine_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdSine.Click
FirstNumber = txtFirstNumber.Text
Answer = (Math.Sin(FirstNumber)) * (Math.PI / 180)
txtAnswer.Text = Answer

End Sub

Which should come out with the right answer, so to test it I did Sin 90 (or tried to) which should come out with 1 exactly, but it came out as 0.01560.....

Is it a mistake in VB, or am I missing something here?

 

[TrainTrackHack]

Isn't it 180/Pi...?

 

[Aastii]

Isn't it 180/Pi...?

I am about 99% sure it is pi/180. Even if I am wrong though and you are right, I just tried it and it comes out as 51.something rather than 1, so that isn't the problem

 

[TrainTrackHack]

Hmm.

What types are FirstNumber and Answer anyways? They should both be explicitly declared as either doubles or floats, I've seen funky things happen with decimal numbers when there's a couple of integers. I haven't programmed much with .NET languages, so I'm not sure, though...

Anyways, explicitly declaring variables is a good programming practice, even if that's not the problem you should do it.

 

[Aastii]

Hmm.

What types are FirstNumber and Answer anyways? They should both be explicitly declared as either doubles or floats, I've seen funky things happen with decimal numbers when there's a couple of integers. I haven't programmed much with .NET languages, so I'm not sure, though...

Anyways, explicitly declaring variables is a good programming practice, even if that's not the problem you should do it.

First Number and answer are both double

Got them as:

Dim FirstNumber As Double = 0
Dim SecondNumber As Double = 0 (this isn't used in this particular one, but is for multiplying, asdding etc)
Dim Answer As Double = 0

So all should be alright there because they aren't decimal or integer

oh, I asked about whether it is 180/pi or pi/180 to my maths tutor today, he says it is 180/pi and showed me why and that, so turns out you were right