C++ automatically rounding off values

[charmedcharmer]

how to resolve the case of c++ rounding off values, for example:

cos(6.2832) i get 1 instead of .99999

and

0.1 being only 0... what should i do

[charmedcharmer]

forgot to say thannk you!

[CornedBee]

It's only rounding on output, the variable contains a better value. Use the setprecision modifier from <iomanip> to select how many places after the comma are displayed.

On a side note, the Windows calculator claims that the result of cos(6.2832) is 0.99399308850723265435071042275478

[charmedcharmer]

thanks... but sometimes it still prints 0 if it is 0.000001. what could be the problem? Thank you for your reply.

[CornedBee]

Floating values only store a specific precision. I don't know the details, as they differ from compiler to compiler.

[NoteMe]

I think that varies from OS too OS too, at least we had that problem in Java at school, on some versions of NT/2000 it wrote 1, and on som e 1.000000000001

[charmedcharmer]

shocks... there are still inconsitencies... anyways.... thanks! at least im able to use <iomanip> even though it doesnt work as always. thanks

[Halsafar]

What about in DirectX
D3DVECTOR struct has a float x,y,z.

Seeing a vector represents character posistion I need to store movement variables as floats.

To eliminate warning of double to float, I have to make everything a float which is part of a units movement system.

Speed, TimeDelta, Velocity, Weight.....the list goes on.


So you are saying that float precision is different from machine to machine...

I need integral values, but I also need a definite precision on any CPU, how do I go about that?

[CornedBee]

Use a decimal number libray like Gnu MPL.

[NoteMe]

Originally posted by Halsafar
What about in DirectX
D3DVECTOR struct has a float x,y,z.

Seeing a vector represents character posistion I need to store movement variables as floats.

To eliminate warning of double to float, I have to make everything a float which is part of a units movement system.

Speed, TimeDelta, Velocity, Weight.....the list goes on.


So you are saying that float precision is different from machine to machine...

I need integral values, but I also need a definite precision on any CPU, how do I go about that?

Floats in DX is pretty much the same. It is a DX standard. Even tho some HW vendors like to try to change that. So don't worry to much about vectors and matrix math in DX. Your GPU is handeling most of that...