private Func <double, double> SumOfAbs(int n)
{
double SumOfn(double x)
{
var s = 0d;
for (int k = 2; k <= n; k++)
{
s += Math.Abs(WalshSobolev.Get2(k)(x));
}
return(s);
}
return(SumOfn);
}
private Func <double, double> PartialSum(Func <double, double> f, int n)
{
var coeffs = new List <double> {
f(0)
};
coeffs.AddRange(Range(1, n).Select(j => coeff(f, j)));
//var coeffs = Range(1, n - 1).Select(j => coeffByDef(j)).ToArray();
double partSum(double x)
{
var s = 0d;
for (int j = 0; j <= n; j++)
{
s += coeffs[j] * WalshSobolev.Get2(j)(x);
}
return(s);
}
return(partSum);
}