/// <summary>
/// Returns similarity function of two vectors.
/// </summary>
/// <param name="p">Vector</param>
/// <param name="b">Vector</param>
/// <returns>Value</returns>
public static float Cosine(this float[] p, float[] b)
{
int length = p.Length;
float A = Matrice.Abs(p, false);
float B = Matrice.Abs(b, false);
float s = 0;
for (int i = 0; i < length; i++)
{
s += p[i] * b[i];
}
return(s / (A * B));
}
