RosettaCodeData/Task/First-class-functions/Java/first-class-functions-2.java

28 lines
817 B
Java

import java.util.ArrayList;
import java.util.function.Function;
public class FirstClass{
public static void main(String... arguments){
ArrayList<Function<Double, Double>> functions = new ArrayList<>();
functions.add(Math::cos);
functions.add(Math::tan);
functions.add(x -> x * x);
ArrayList<Function<Double, Double>> inverse = new ArrayList<>();
inverse.add(Math::acos);
inverse.add(Math::atan);
inverse.add(Math::sqrt);
System.out.println("Compositions:");
for (int i = 0; i < functions.size(); i++){
System.out.println(functions.get(i).compose(inverse.get(i)).apply(0.5));
}
System.out.println("Hard-coded compositions:");
System.out.println(Math.cos(Math.acos(0.5)));
System.out.println(Math.tan(Math.atan(0.5)));
System.out.println(Math.pow(Math.sqrt(0.5), 2));
}
}