public void AdditionTest_Success()
{
Matrix4 a = new Matrix4(new double[,]
{
{1.0, 2.0, 3.0, 4.0},
{5.0, 6.0, 7.0, 8.0},
{9.0, 10.0, 11.0, 12.0},
{13.0, 14.0, 15.0, 16.0}
});
Matrix4 b = new Matrix4(new double[,]
{
{1.0, 2.0, 3.0, 4.0},
{5.0, 6.0, 7.0, 8.0},
{9.0, 10.0, 11.0, 12.0},
{13.0, 14.0, 15.0, 16.0}
});
Matrix4 result = a + b;
Matrix4 expected = new Matrix4(new double[,]
{
{2.0, 4.0, 6.0, 8.0},
{10.0, 12.0, 14.0, 16.0},
{18.0, 20.0, 22.0, 24.0},
{26.0, 28.0, 30.0, 32.0}
});
Assert.AreEqual(expected, result);
}
public void DeterminantTest_Success()
{
Matrix4 mat = new Matrix4(new double[,]
{
{ -2.0, 2.0, -3.0, 3.0 },
{ -1.0, 1.0, 3.0, -3.0 },
{ 2.0, 0.0, -1.0, 1.0 },
{ -3.0, 2.0, -1.0, 0.0 }
});
double expected = -18.0;
double actual = mat.Determinant();
Assert.AreEqual(expected, actual, 0.001);
}
public void DivisionTest()
{
Matrix4 a = new Matrix4(new double[,]
{
{1.0, 2.0, 3.0, 4.0},
{5.0, 6.0, 7.0, 8.0},
{9.0, 10.0, 11.0, 12.0},
{13.0, 14.0, 15.0, 16.0}
});
Matrix4 result = a / 2;
Matrix4 expected = new Matrix4(new double[,]
{
{ 0.5, 1.0, 1.5, 2.0 },
{ 2.5, 3.0, 3.5, 4.0 },
{ 4.5, 5.0, 5.5, 6.0 },
{ 6.5, 7.0, 7.5, 8.0 }
});
Assert.AreEqual(expected, result);
}
public void Transpose_Success()
{
Matrix4 mat = new Matrix4(new double[,]
{
{ 1.0, 2.0, 3.0, 4.0 },
{ 5.0, 6.0, 7.0, 8.0 },
{ 9.0, 10.0, 11.0, 12.0 },
{ 13.0, 14.0, 15.0, 16.0}
});
Matrix4 transpose = mat.Transpose();
Assert.AreEqual(1.0, transpose[0, 0], Epsilon);
Assert.AreEqual(5.0, transpose[0, 1], Epsilon);
Assert.AreEqual(7.0, transpose[2, 1], Epsilon);
Assert.AreEqual(9.0, transpose[0, 2], Epsilon);
}
public void Transpose_Empty_Success()
{
Matrix4 mat = new Matrix4();
Matrix4 transpose = mat.Transpose();
Assert.AreEqual(0.0, transpose[0, 0], Epsilon);
Assert.AreEqual(0.0, transpose[0, 1], Epsilon);
Assert.AreEqual(0.0, transpose[2, 1], Epsilon);
Assert.AreEqual(0.0, transpose[0, 2], Epsilon);
}
public void SubtractionTest_Success()
{
Matrix4 a = new Matrix4(new double[,]
{
{1.0, 2.0, 3.0, 4.0},
{5.0, 6.0, 7.0, 8.0},
{9.0, 10.0, 11.0, 12.0},
{13.0, 14.0, 15.0, 16.0}
});
Matrix4 b = new Matrix4(new double[,]
{
{4.0, 3.0, 2.0, 1.0},
{8.0, 7.0, 6.0, 5.0},
{12.0, 11.0, 10.0, 9.0},
{16.0, 15.0, 14.0, 13.0}
});
Matrix4 result = a - b;
Matrix4 expected = new Matrix4(new double[,]
{
{-3.0, -1.0, 1.0, 3.0},
{-3.0, -1.0, 1.0, 3.0},
{-3.0, -1.0, 1.0, 3.0},
{-3.0, -1.0, 1.0, 3.0},
});
Assert.AreEqual(expected, result);
}
public void MultiplyTest_VectorByMatrix()
{
Vector4 a = new Vector4(1.0, 2.0, 3.0, 4.0);
Matrix4 b = new Matrix4(new double[,]
{
{1.0, 2.0, 3.0, 4.0},
{5.0, 6.0, 7.0, 8.0},
{9.0, 10.0, 11.0, 12.0},
{13.0, 14.0, 15.0, 16.0}
});
Vector4 result = a * b;
Vector4 expected = new Vector4(90.0, 100.0, 110.0, 120.0);
Assert.AreEqual(expected, result);
result = b * a;
expected = new Vector4(30.0, 70.0, 110.0, 150.0);
Assert.AreEqual(expected, result);
}
public bool Equals(Matrix4 other, double epsilon)
{
if (other == null)
{
return false;
}
else
{
for (int y = 0; y < Height; y++)
{
for (int x = 0; x < Width; x++)
{
double diff = System.Math.Abs(_values[y, x] - other[y, x]);
if (diff > epsilon)
{
return false;
}
}
}
return true;
}
}
public void VectorArrayConstructor_TooFew_Success()
{
Vector4[] values = new Vector4[] {
new Vector4(1.0, 2.0, 3.0, 4.0),
new Vector4(5.0, 6.0, 7.0, 8.0),
new Vector4(9.0, 10.0, 11.0, 12.0),
};
Matrix4 mat = new Matrix4(values);
Assert.AreEqual(1.0, mat[0, 0]);
Assert.AreEqual(7.0, mat[1, 2]);
Assert.AreEqual(0.0, mat[3, 0]);
}
public void ZeroConstructorTest_Success()
{
Matrix4 mat = new Matrix4();
for (int x = 0; x < 4; x++)
{
for (int y = 0; y < 4; y++)
{
Assert.AreEqual(0.0, mat[x, y]);
}
}
}
public void MultiDoubleArrayConstructor_TooFew_Success()
{
double[,] values = new double[,] {
{ 1.0,2.0,3.0,4.0 },
{5.0,6.0,7.0,8.0},
{9.0,10.0,11.0,12.0}
};
Matrix4 mat = new Matrix4(values);
Assert.AreEqual(1.0, mat[0, 0]);
Assert.AreEqual(7.0, mat[1, 2]);
Assert.AreEqual(0.0, mat[3, 0]);
}
public void VectorArrayConstructor_NullInArray_Throws()
{
Vector4[] values = new Vector4[] {
new Vector4(1.0, 2.0, 3.0, 4.0),
new Vector4(5.0, 6.0, 7.0, 8.0),
null,
new Vector4(13.0, 14.0, 15.0, 16.0),
};
Matrix4 mat = new Matrix4(values);
}
public void MultiDoubleArrayConstructor_Null_Throws()
{
double[,] values = null;
Matrix4 mat = new Matrix4(values);
}
public void InversionTest_Success()
{
Matrix4 mat = new Matrix4(new double[,]
{
{ -2.0, 2.0, -3.0, -3.0 },
{ -1.0, -1.0, 3.0, 3.0 },
{ 2.0, 0.0, -1.0, 1.0 },
{ 3.0, 2.0, 1.0, 0.0 }
});
Matrix4 inverse = mat.Inverse();
Matrix4 product = mat * inverse;
Assert.AreEqual(Matrix4.Identity, product);
}
public void InversionTest_NonInvertible_Throws()
{
Matrix4 mat = new Matrix4(new double[,]
{
{ -2.0, 2.0, -3.0, 3.0 },
{ -1.0, 1.0, 3.0, -3.0 },
{ 2.0, 0.0, -1.0, 1.0 },
{ -3.0, 2.0, -1.0, 0.0 }
});
mat.Inverse();
}
public void DoubleArrayConstructor_TooMany_Throws()
{
double[] values = new double[] {
1.0,2.0,3.0,4.0,
5.0,6.0,7.0,8.0,
9.0,10.0,11.0,12.0,
13.0,14.0,15.0,16.0,
17.0
};
Matrix4 mat = new Matrix4(values);
}
public void DoubleArrayConstructor_Success()
{
double[] values = new double[] {
1.0,2.0,3.0,4.0,
5.0,6.0,7.0,8.0,
9.0,10.0,11.0,12.0,
13.0,14.0,15.0,16.0,
};
Matrix4 mat = new Matrix4(values);
Assert.AreEqual(1.0, mat[0, 0]);
Assert.AreEqual(7.0, mat[1, 2]);
Assert.AreEqual(14.0, mat[3, 1]);
}
public void VectorArrayConstructor_Null_Throws()
{
Vector4[] values = null;
Matrix4 mat = new Matrix4(values);
}
public void MultiDoubleArrayConstructor_TooManyRows_Throws()
{
double[,] values = new double[,] {
{ 1.0,2.0,3.0,4.0 },
{5.0,6.0,7.0,8.0},
{9.0,10.0,11.0,12.0},
{13.0,14.0,15.0,16.0},
{17.0, 18.0, 19.0, 20.0 }
};
Matrix4 mat = new Matrix4(values);
}
public void VectorArrayConstructor_TooMany_Throws()
{
Vector4[] values = new Vector4[] {
new Vector4(1.0, 2.0, 3.0, 4.0),
new Vector4(5.0, 6.0, 7.0, 8.0),
new Vector4(9.0, 10.0, 11.0, 12.0),
new Vector4(13.0, 14.0, 15.0, 16.0),
new Vector4(17.0, 18.0, 18.0, 20.0),
};
Matrix4 mat = new Matrix4(values);
}
public void MultiplicationTest()
{
Matrix4 a = new Matrix4(new double[,]
{
{1.0, 2.0, 3.0, 4.0},
{5.0, 6.0, 7.0, 8.0},
{9.0, 10.0, 11.0, 12.0},
{13.0, 14.0, 15.0, 16.0}
});
Matrix4 result = a * 2;
Matrix4 expected = new Matrix4(new double[,]
{
{ 2.0, 4.0, 6.0, 8.0 },
{ 10.0, 12.0, 14.0, 16.0 },
{ 18.0, 20.0, 22.0, 24.0 },
{ 26.0, 28.0, 30.0, 32.0 }
});
Assert.AreEqual(expected, result);
result = a * 0;
expected = new Matrix4();
Assert.AreEqual(expected, result);
}
public void MultiplyByIdentity_ReturnsSame()
{
Matrix4 a = new Matrix4(new double[,]
{
{1.0, 2.0, 3.0, 4.0},
{5.0, 6.0, 7.0, 8.0},
{9.0, 10.0, 11.0, 12.0},
{13.0, 14.0, 15.0, 16.0}
});
Matrix4 result = a * Matrix4.Identity;
Assert.AreEqual(a, result);
}
public void MultiplyTest_MatrixByMatrix()
{
Matrix4 a = new Matrix4(new double[,]
{
{1.0, 2.0, 3.0, 4.0},
{5.0, 6.0, 7.0, 8.0},
{9.0, 10.0, 11.0, 12.0},
{13.0, 14.0, 15.0, 16.0}
});
Matrix4 b = new Matrix4(new double[,]
{
{4.0, 3.0, 2.0, 1.0},
{8.0, 7.0, 6.0, 5.0},
{12.0, 11.0, 10.0, 9.0},
{16.0, 15.0, 14.0, 13.0}
});
var result = a * b;
Matrix4 expected = new Matrix4(new double[,]
{
{ 120.0, 110.0, 100.0, 90.0 },
{ 280.0, 254.0, 228.0, 202.0 },
{ 440.0, 398.0, 356.0, 314.0 },
{ 600.0, 542.0, 484.0, 426.0 }
});
Assert.AreEqual(expected, result);
result = b * a;
expected = new Matrix4(new double[,] {
{ 50.0, 60.0, 70.0, 80.0 },
{ 162.0, 188.0, 214.0, 240.0 },
{ 274.0, 316.0, 358.0, 400.0 },
{ 386.0, 444.0, 502.0, 560.0 }
});
Assert.AreEqual(expected, result);
}
public void DivisionTest_DivideByZero_Throws()
{
Matrix4 a = new Matrix4(new double[,]
{
{1.0, 2.0, 3.0, 4.0},
{5.0, 6.0, 7.0, 8.0},
{9.0, 10.0, 11.0, 12.0},
{13.0, 14.0, 15.0, 16.0}
});
Matrix4 result = a / 0;
}
/// <summary>
/// Calculates the transpose of the input matrix.
/// </summary>
/// <returns>A matrix that is the tranpose of the input matrix.</returns>
public static Matrix4 Transpose(Matrix4 mat)
{
if (mat == null)
{
throw new ArgumentNullException("mat");
}
double[,] transpose = new double[4, 4];
for (int y = 0; y < 4; y++)
{
for (int x = 0; x < 4; x++)
{
transpose[x, y] = mat[y, x];
}
}
return new Matrix4(transpose);
}
