Double-Double Ordinary Differential Equation Solver
.NET 8.0
DoubleDouble
DormandPrinceODESolver solver = new(v: 1, (x) => x);
for (int i = 0; i < 256; i++) {
solver.Next(1d / 256);
}
Assert.AreEqual(0d, (double)(solver.X - ddouble.E), 1e-12);