public static double GetInnerDot(DoubleVec vec1, DoubleVec vec2)
{
double innerDot = 0.0d;
double[] vec1a = vec1.GetVec();
double[] vec2a = vec2.GetVec();
// proceed the calculation only if same size
if (vec1.GetSize() == vec2.GetSize())
{
for (int i = 0; i < vec1.GetSize(); i++)
{
innerDot += (vec1a[i] * vec2a[i]);
}
}
return(innerDot);
}
// private methods
private static void Test()
{
DoubleVec vec = new DoubleVec(5);
Console.WriteLine("- size: " + vec.GetSize());
Console.WriteLine("- vec: " + vec.ToString());
double[] a1 = new double[] { 1.0d, 2.0d, 3.0d };
DoubleVec v1 = new DoubleVec(a1);
Console.WriteLine("- size: " + v1.GetSize());
Console.WriteLine("- v1: " + v1.ToString());
a1[0] = 5.0d;
Console.WriteLine("- v1 (check ref): " + v1.ToString());
double[] a2 = new double[] { 3.0d, 5.0d, 3.0d };
DoubleVec v2 = new DoubleVec(a2);
Console.WriteLine("- v2: " + v2.ToString() + ", size:" + v2.GetSize());
v2.Add(v1);
Console.WriteLine("- Add, v1: " + v1.ToString());
Console.WriteLine("- Add, v2: " + v2.ToString());
v2.Minus(v1);
Console.WriteLine("- Minus, v1: " + v1.ToString());
Console.WriteLine("- Minus, v2: " + v2.ToString());
v2.Divide(4);
Console.WriteLine("- Div, v1: " + v1.ToString());
Console.WriteLine("- Div, v2: " + v2.ToString());
}
public virtual void Minus(DoubleVec vec)
{
if ((vec != null) && (GetSize() == vec.GetSize()))
{
for (int i = 0; i < GetSize(); i++)
{
vec_[i] = vec_[i] - vec.GetElement(i);
}
}
}
// public methods
public static DoubleVec Divide(DoubleVec vec, int count)
{
DoubleVec outVec = null;
if ((count != 0) && (vec != null))
{
outVec = new DoubleVec(vec.GetSize());
for (int i = 0; i < outVec.GetSize(); i++)
{
outVec.SetElement(vec.GetElement(i) / count, i);
}
}
return(outVec);
}
public static DoubleVec Minus(DoubleVec vec1, DoubleVec vec2)
{
int size1 = vec1.GetSize();
int size2 = vec2.GetSize();
DoubleVec outVec = new DoubleVec(size1);
if (size1 == size2)
{
for (int i = 0; i < size1; i++)
{
double @out = vec1.GetElement(i) - vec2.GetElement(i);
outVec.SetElement(@out, i);
}
}
return(outVec);
}
//the output is between 0.0 ~ 1.0
public static double GetCosineSimilarity(DoubleVec vec1, DoubleVec vec2)
{
double similarity = 0.0d;
double length1 = GetLength(vec1);
double length2 = GetLength(vec2);
//must has same size
if ((vec1 != null) && (vec2 != null) && (length1 > 0.0d) && (length2 > 0.0d) && (vec1.GetSize() == vec2.GetSize()))
{
similarity = GetInnerDot(vec1, vec2) / (length1 * length2);
}
return(similarity);
}