N.A.N value ---SOLVED---

[short]

Code: Select all

if( x == 0 && y == 0 && Vector.getZ() == 0 )

Technically, you should use float comparison

I did not get a compiler warning. Vector.getZ() also returns a float.

That's because an explicit conversion is happening.

Agreed that I should probably put my magnitude calculation into a function/method so it can return the magnitude. The reason for not sqrt'ing it is so I can use the if statement to make sure my number does not come out N.A.N.

How would squaring two floats EVER return in NAN?

[Falco Girgis]

^ He has some very good points. You really do need to start using epsilon-based floating-point comparisons.

[THe Floating Brain]

I tried it but I get a error with:

Code: Select all

inline bool operator==(const Vector &lhs, const int r) {
    return ((lhs.x - r) < FLT_EPSILON)  && ((lhs.y - r) < FLT_EPSILON) && ((lhs.z - r) < FLT_EPSILON);
}

I don't usually use operator command ( I should probably use it more it is a nessary skill ), and I am unfamiliar with how to fix this:

Code: Select all

1>------ Build started: Project: Vector Scan Area, Configuration: Debug Win32 ------
1>Compiling...
1>Main.cpp
1>c:\users\aperson\documents\visual studio 2008\projects\vector scan area\vector scan area\vector calculator.h(24) : error C2804: binary 'operator ==' has too many parameters
1>c:\users\aperson\documents\visual studio 2008\projects\vector scan area\vector scan area\vector calculator.h(24) : error C2333: 'Math::Vector::Vector_Calculator::operator ==' : error in function declaration; skipping function body
1>c:\users\aperson\documents\visual studio 2008\projects\vector scan area\vector scan area\vector calculator.h(36) : error C2678: binary '==' : no operator found which takes a left-hand operand of type 'Containers::Base::XYZ' (or there is no acceptable conversion)
1>        c:\program files\microsoft sdks\windows\v6.0a\include\guiddef.h(192): could be 'int operator ==(const GUID &,const GUID &)'
1>        while trying to match the argument list '(Containers::Base::XYZ, int)'
1>Build log was saved at "file://c:\Users\aperson\Documents\Visual Studio 2008\Projects\Vector Scan Area\Vector Scan Area\Debug\BuildLog.htm"
1>Vector Scan Area - 3 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

I feel like such a noob

[Ginto8]

the error is saying you're providing too many arguments. As it is, you'd have to say it Vec1 == Vec2, 3. And that's just plain wrong. r, the const int, is supposed to be provided in the source file, not as a parameter to the operator.

[THe Floating Brain]

So you are saying this is incorrect:

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//Modified to fit my program. I did test this with a struct instead of a class I get the same result.//
inline bool operator==( const Containers::Base::XYZ &lhs, const int r ) {
				return ((lhs.getX() - r) < FLT_EPSILON)  && ((lhs.getY() - r) < FLT_EPSILON) && ((lhs.getZ() - r) < FLT_EPSILON);
}
Containers::Base::XYZ Vector_Calculation( Containers::Base::XYZ Goto, Containers::Base::XYZ Position, float Speed )
{
...
if( Vector == 0 )
   return Vector;
...
}

Or are you saying this should be declared outside the class "Vector_Calculator" in the source file?
???

[short]

Yes. Define the method outside the class, inside the same namespace. Preferably within the same source file. The reason for this is you can completely define the == operator in terms of vectors public interface.

My experience tells me, if you can declare a function in terms of its pre-existing public interface, and it makes sense to do so, then do it. There is no reason to lower encapsulation by making the == operator a member function of the vector class.

To fit your example from you first post

Code: Select all

namespace Math
{
   namespace Vector
   {
      class Vector_Calculator
      {
      public:
          .... blah blah blah
      }; // end of class

    // put operator overload here
    inline bool operator==(const Vector &lhs, const int r) {
        return ((lhs.x - r) < FLT_EPSILON)  && ((lhs.y - r) < FLT_EPSILON) && ((lhs.z - r) < FLT_EPSILON);
    }
    
   }
}

[THe Floating Brain]

Thank you :-D