public void CanCheckRankOfSquareSingular([Values(10, 50, 100)] int order)
{
var A = new DenseMatrix(order, order);
A[0, 0] = 1;
A[order - 1, order - 1] = 1;
for (var i = 1; i < order - 1; i++)
{
A[i, i - 1] = 1;
A[i, i + 1] = 1;
A[i - 1, i] = 1;
A[i + 1, i] = 1;
}
var factorEvd = A.Evd();
Assert.AreEqual(factorEvd.Determinant, 0);
Assert.AreEqual(factorEvd.Rank, order - 1);
}