// 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);
}
}
}
//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);
}
// 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);
}
public static double GetLength(DoubleVec inVec)
{
double length = 0.0d;
double sum = 0.0d;
double[] vec = inVec.GetVec();
for (int i = 0; i < vec.Length; i++)
{
sum += (vec[i] * vec[i]);
}
if (sum > 0.0)
{
length = Math.Sqrt(sum);
}
return(length);
}
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()
{
double[] a1 = new double[] { 1.0d, 1.0d, 1.0d };
double[] a2 = new double[] { 1.0d, 2.0d, 3.0d };
double[] a3 = new double[] { 9.0d, 18.0d, 27.0d };
double[] a4 = new double[] { 0.0d, 1.0d, 0.0d };
double[] a5 = new double[] { 0.0d, -1.0d, 0.0d };
DoubleVec v1 = new DoubleVec(a1);
DoubleVec v2 = new DoubleVec(a2);
DoubleVec v3 = new DoubleVec(a3);
DoubleVec v4 = new DoubleVec(a4);
DoubleVec v5 = new DoubleVec(a5);
Console.WriteLine("v1: " + v1.ToString() + ", length: " + GetLength(v1));
Console.WriteLine("v2: " + v1.ToString() + ", length: " + GetLength(v2));
Console.WriteLine("v3: " + v1.ToString() + ", length: " + GetLength(v3));
Console.WriteLine("v4: " + v1.ToString() + ", length: " + GetLength(v4));
Console.WriteLine("v5: " + v1.ToString() + ", length: " + GetLength(v5));
Console.WriteLine("v1.v2: dot: " + GetInnerDot(v1, v2) + ", s: " + GetCosineSimilarity(v1, v2));
Console.WriteLine("v2.v3: dot: " + GetInnerDot(v2, v3) + ", s: " + GetCosineSimilarity(v2, v3));
Console.WriteLine("v3.v4: dot: " + GetInnerDot(v3, v4) + ", s: " + GetCosineSimilarity(v3, v4));
Console.WriteLine("v4.v5: dot: " + GetInnerDot(v4, v5) + ", s: " + GetCosineSimilarity(v4, v5));
double[] a6 = new double[] { 2.0d, 1.0d, 0.0d, 2.0d, 0.0d, 1.0d, 1.0d, 1.0d };
double[] a7 = new double[] { 2.0d, 1.0d, 1.0d, 1.0d, 1.0d, 0.0d, 1.0d, 1.0d };
DoubleVec v6 = new DoubleVec(a6);
DoubleVec v7 = new DoubleVec(a7);
Console.WriteLine("v6: " + v6.ToString());
Console.WriteLine("v7: " + v7.ToString());
Console.WriteLine("v6.v7: dot: " + GetInnerDot(v6, v7) + ", s (0.822): " + GetCosineSimilarity(v6, v7));
DoubleVec v8 = Add(v6, v7);
Console.WriteLine("Add v8: " + v8.ToString());
DoubleVec v9 = Divide(v8, 4);
Console.WriteLine("Divide v9: " + v9.ToString());
Console.WriteLine("v8: " + v8.ToString());
DoubleVec v10 = Minus(v8, v7);
Console.WriteLine("Minus v10: " + v10.ToString());
}