public static double DotProduct(this Matrix a, Matrix b)
{
if (!a.IsVector || !b.IsVector)
{
throw new ArgumentException("two vectors expected");
}
//var length = a.Data.GetLength(0);
//if ((length != a.Data.GetLength(1) && a.Data.GetLength(1) != 1) || (b.Data.GetLength(0) != a.Data.GetLength(1) && a.Data.GetLength(0) != 1))
// throw new ArgumentException();
//if (length != b.Data.GetLength(1))
// throw new ArgumentException("vectors don't have same length");
//var result = 0.0;
//for (var i = 0; i < length; i++)
// result += a.Data[i, 0] * b.Data[0, i];
//return result;
var aArray = a.ToPackedArray();
var bArray = b.ToPackedArray();
if (aArray.Length != bArray.Length)
{
throw new ArgumentException("vectors don't have same length");
}
var result = 0.0;
for (var i = 0; i < aArray.Length; i++)
{
result += aArray[i] * bArray[i];
}
return(result);
}
public static double VectorLength(this Matrix input)
{
if (!input.IsVector)
{
throw new ArgumentException("input is not a vector");
}
var v = input.ToPackedArray();
return(Math.Sqrt(v.Sum(t => Math.Pow(t, 2))));
}
public static double DotProduct(this Matrix a, Matrix b)
{
if (!a.IsVector || !b.IsVector)
throw new ArgumentException("two vectors expected");
//var length = a.Data.GetLength(0);
//if ((length != a.Data.GetLength(1) && a.Data.GetLength(1) != 1) || (b.Data.GetLength(0) != a.Data.GetLength(1) && a.Data.GetLength(0) != 1))
// throw new ArgumentException();
//if (length != b.Data.GetLength(1))
// throw new ArgumentException("vectors don't have same length");
//var result = 0.0;
//for (var i = 0; i < length; i++)
// result += a.Data[i, 0] * b.Data[0, i];
//return result;
var aArray = a.ToPackedArray();
var bArray = b.ToPackedArray();
if (aArray.Length != bArray.Length)
throw new ArgumentException("vectors don't have same length");
var result = 0.0;
for (var i = 0; i < aArray.Length; i++)
result += aArray[i] * bArray[i];
return result;
}
