Question

I have been trying to learn more about lambda expressions lately, and thought of a interesting exercise…

is there a way to simplify a c++ integration function like this:

// Integral Function double integrate(double a, double b, double (*f)(double)) {     double sum = 0.0;      // Evaluate integral{a,b} f(x) dx     for(int n = 0 ; n <= 100; ++n)     {         double x = a + n*(b-a)/100.0;         sum += (*f)(x) * (b-a)/101.0;     }     return sum; } 

by using c# and lambda expressions?

Answer 1

What about this:

public double Integrate(double a,double b, Func<double, double> f) {     double sum = 0.0;      for (int n = 0; n <= 100; ++n)     {         double x = a + n * (b - a) / 100.0;         sum += f(x) * (b - a) / 101.0;     }     return sum; } 

Test:

    Func<double, double> fun = x => Math.Pow(x,2);             double result = Integrate(0, 10, fun);