public static double[] GetRoots(double[] сoefficients, double precision = 0.00000000000001, double InitialStep = 1, double MinStep = 0.25, SolverOptions options = SolverOptions.StopIfNumberOfRootsCeasedIncrease)
{
RootsLimits Limits = GetRootsLimits(сoefficients);
//отделение корнеЙ
double h = InitialStep;
Interval[] IntervalsWithNormalStep;
Interval[] IntervalsWithHalfOfStep;
//лямбда полинома с коефициентами
var lambda = FormLambdaForPolinom(сoefficients.ToArray());
do
{
IntervalsWithNormalStep = GetIntervalsWithRoots(lambda, h, Limits.NLower, Limits.NUpper, Limits.PLower, Limits.PUpper);
IntervalsWithHalfOfStep = GetIntervalsWithRoots(lambda, h / 2, Limits.NLower, Limits.NUpper, Limits.PLower, Limits.PUpper);
h /= 2;
}while (IntervalsWithNormalStep.Length != IntervalsWithHalfOfStep.Length);
//уточнение корней
double[] roots = ClarifyRoots(lambda, IntervalsWithHalfOfStep, precision);
return(roots);
}
public static double[] GetRoots(double[] сoefficients, int numberOfroots, int startIntervalsCount = 64, double precision = 0.00000001)
{
RootsLimits Limits = GetRootsLimits(сoefficients);
List <Interval> intervals = new List <Interval>();
//лямбда полинома с коефициентами
var lambda1 = FormLambdaForPolinom(сoefficients.ToArray());
var lambda2 = FormLambdaForPolinom(сoefficients.ToArray());
Func <double, double, Func <double, double>, List <Interval> > getIntervals = (a, b, polinom) =>
{
double h = (b - a) / startIntervalsCount;
double lBrd = 0;
double rBrd = 0;
List <Interval> result = new List <Interval>();
//для отрицательной части
for (double i = a; i < b; i = rBrd)
{
lBrd = i;
rBrd = i + h;
if (polinom(lBrd) * polinom(rBrd) < 0)
{
result.Add(new Interval(lBrd, rBrd));
}
}
return(result);
};
do
{
intervals.Clear();
Task <List <Interval> > t1 = Task <List <Interval> > .Run(() => getIntervals(Limits.NLower, Limits.NUpper, lambda1));
Task <List <Interval> > t2 = Task <List <Interval> > .Run(() => getIntervals(Limits.PLower, Limits.PUpper, lambda2));
Task.WaitAll((new[] { t1, t2 }));
intervals.AddRange(t1.Result);
intervals.AddRange(t2.Result);
startIntervalsCount *= 2;
}while (numberOfroots != intervals.Count);
//уточнение корней
double[] roots = ClarifyRoots(lambda1, intervals.ToArray(), precision);
return(roots);
}
private static RootsLimits GetRootsLimits(double[] сoefficients)
{
var Limits = new RootsLimits();
//то же что и умножить на икс в высшей степени и подставить 1/x
var ReverceCoefs = сoefficients.Reverse().ToArray();; //Для фи1 и фи3
//поиск границ корней
Limits.PUpper = UpperLimitSearcher.GetUpperLimit(сoefficients);
Limits.PLower = 1d / UpperLimitSearcher.GetUpperLimit(ReverceCoefs);
Limits.NLower = -UpperLimitSearcher.GetUpperLimit(SubstituteNegativeArgument(сoefficients)); //минус там не зря)
Limits.NUpper = -1d / UpperLimitSearcher.GetUpperLimit(SubstituteNegativeArgument(ReverceCoefs));
return(Limits);
}
