//JAVA TO C# CONVERTER TODO TASK: Most Java annotations will not have direct .NET equivalent attributes:
//ORIGINAL LINE: @Test public void testHashCodeAndEquals()
public virtual void testHashCodeAndEquals()
{
//JAVA TO C# CONVERTER WARNING: The original Java variable was marked 'final':
//ORIGINAL LINE: final double[] a = java.util.Arrays.copyOf(A, A.length);
double[] a = Arrays.copyOf(A, A.Length);
//JAVA TO C# CONVERTER WARNING: The original Java variable was marked 'final':
//ORIGINAL LINE: final double[] b = java.util.Arrays.copyOf(B, B.length);
double[] b = Arrays.copyOf(B, B.Length);
//JAVA TO C# CONVERTER WARNING: The original Java variable was marked 'final':
//ORIGINAL LINE: final double[] c = java.util.Arrays.copyOf(C, C.length);
double[] c = Arrays.copyOf(C, C.Length);
TridiagonalMatrix other = new TridiagonalMatrix(a, b, c);
assertEquals(other, M);
assertEquals(other.GetHashCode(), M.GetHashCode());
a[1] = 1000;
other = new TridiagonalMatrix(a, B, C);
assertFalse(other.Equals(M));
b[1] = 1000;
other = new TridiagonalMatrix(A, b, C);
assertFalse(other.Equals(M));
c[1] = 1000;
other = new TridiagonalMatrix(A, B, c);
assertFalse(other.Equals(M));
}
public override bool Equals(object obj)
{
if (this == obj)
{
return(true);
}
if (obj == null)
{
return(false);
}
if (this.GetType() != obj.GetType())
{
return(false);
}
TridiagonalMatrix other = (TridiagonalMatrix)obj;
if (!Arrays.Equals(_a, other._a))
{
return(false);
}
if (!Arrays.Equals(_b, other._b))
{
return(false);
}
if (!Arrays.Equals(_c, other._c))
{
return(false);
}
return(true);
}
/// <summary>
/// Solves the system Ax = y for the unknown vector x, where A is a tridiagonal matrix and y is a vector.
/// This takes order n operations where n is the size of the system
/// (number of linear equations), as opposed to order n^3 for the general problem. </summary>
/// <param name="aM"> tridiagonal matrix </param>
/// <param name="b"> known vector (must be same length as rows/columns of matrix) </param>
/// <returns> vector (as an array of doubles) with same length as y </returns>
public static double[] solvTriDag(TridiagonalMatrix aM, double[] b)
{
ArgChecker.notNull(aM, "null matrix");
ArgChecker.notNull(b, "null vector");
double[] d = aM.Diagonal; //b is modified, so get copy of diagonal
int n = d.Length;
ArgChecker.isTrue(n == b.Length, "vector y wrong length for matrix");
double[] y = Arrays.copyOf(b, n);
double[] l = aM.LowerSubDiagonalData;
double[] u = aM.UpperSubDiagonalData;
double[] x = new double[n];
for (int i = 1; i < n; i++)
{
double m = l[i - 1] / d[i - 1];
d[i] = d[i] - m * u[i - 1];
y[i] = y[i] - m * y[i - 1];
}
x[n - 1] = y[n - 1] / d[n - 1];
for (int i = n - 2; i >= 0; i--)
{
x[i] = (y[i] - u[i] * x[i + 1]) / d[i];
}
return(x);
}
//JAVA TO C# CONVERTER TODO TASK: Most Java annotations will not have direct .NET equivalent attributes:
//ORIGINAL LINE: @Test public void test()
public virtual void test()
{
const int n = 97;
double[] a = new double[n - 1];
double[] b = new double[n];
double[] c = new double[n - 1];
double[] x = new double[n];
for (int ii = 0; ii < n; ii++)
{
b[ii] = RANDOM.nextRandom();
x[ii] = RANDOM.nextRandom();
if (ii < n - 1)
{
a[ii] = RANDOM.nextRandom();
c[ii] = RANDOM.nextRandom();
}
}
//JAVA TO C# CONVERTER WARNING: The original Java variable was marked 'final':
//ORIGINAL LINE: final TridiagonalMatrix m = new TridiagonalMatrix(b, a, c);
TridiagonalMatrix m = new TridiagonalMatrix(b, a, c);
//JAVA TO C# CONVERTER WARNING: The original Java variable was marked 'final':
//ORIGINAL LINE: final com.opengamma.strata.collect.array.DoubleArray xVec = com.opengamma.strata.collect.array.DoubleArray.copyOf(x);
DoubleArray xVec = DoubleArray.copyOf(x);
//JAVA TO C# CONVERTER WARNING: The original Java variable was marked 'final':
//ORIGINAL LINE: final com.opengamma.strata.collect.array.DoubleArray yVec = (com.opengamma.strata.collect.array.DoubleArray) MA.multiply(m, xVec);
DoubleArray yVec = (DoubleArray)MA.multiply(m, xVec);
//JAVA TO C# CONVERTER WARNING: The original Java variable was marked 'final':
//ORIGINAL LINE: final double[] xSolv = solvTriDag(m, yVec).toArray();
double[] xSolv = solvTriDag(m, yVec).toArray();
for (int i = 0; i < n; i++)
{
assertEquals(x[i], xSolv[i], 1e-9);
}
DoubleArray resi = (DoubleArray)MA.subtract(MA.multiply(m, DoubleArray.copyOf(xSolv)), yVec);
double err = MA.getNorm2(resi);
assertEquals(0.0, err, 1e-14);
}
/// <summary>
/// Solves the system Ax = y for the unknown vector x, where A is a tridiagonal matrix and y is a vector.
/// This takes order n operations where n is the size of the system
/// (number of linear equations), as opposed to order n^3 for the general problem. </summary>
/// <param name="aM"> tridiagonal matrix </param>
/// <param name="b"> known vector (must be same length as rows/columns of matrix) </param>
/// <returns> vector with same length as y </returns>
public static DoubleArray solvTriDag(TridiagonalMatrix aM, DoubleArray b)
{
return(DoubleArray.copyOf(solvTriDag(aM, b.toArray())));
}
