Angle between two Vectors 2D

Question

I\'m trying to compute the angle between two vectors. I tried this, but it always returns zero:

public double GetAngle(Vector2 a, Vector2 b)
{
double angle = Mat         


        

Answer 1

I think code show as below copy from .NET source code could help you.

reference: http://referencesource.microsoft.com/#WindowsBase/Base/System/Windows/Vector.cs,102

/// 

/// AngleBetween - the angle between 2 vectors
/// 
/// 
/// Returns the the angle in degrees between vector1 and vector2
/// 
///  The first Vector 
///  The second Vector 
public static double AngleBetween(Vector vector1, Vector vector2)
{
    double sin = vector1._x * vector2._y - vector2._x * vector1._y;  
    double cos = vector1._x * vector2._x + vector1._y * vector2._y;

    return Math.Atan2(sin, cos) * (180 / Math.PI);
}