PowBenchmark

import java.util.concurrent.TimeUnit;

import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Warmup;
import org.openjdk.jmh.runner.Runner;
import org.openjdk.jmh.runner.RunnerException;
import org.openjdk.jmh.runner.options.Options;
import org.openjdk.jmh.runner.options.OptionsBuilder;

//Benchmark            Mode  Cnt   Score   Error  Units
//PowBenchmark.cross2  avgt    5   2.200 ± 0.102  ns/op
//PowBenchmark.cross3  avgt    5   2.322 ± 0.010  ns/op
//PowBenchmark.cross4  avgt    5   2.482 ± 0.101  ns/op
//PowBenchmark.cross5  avgt    5   2.671 ± 0.035  ns/op
//PowBenchmark.pow2    avgt    5   2.184 ± 0.057  ns/op
//PowBenchmark.pow3    avgt    5  64.120 ± 0.326  ns/op
//PowBenchmark.pow4    avgt    5  61.893 ± 0.173  ns/op
//PowBenchmark.pow5    avgt    5  61.924 ± 0.331  ns/op
@BenchmarkMode(Mode.AverageTime)
@Fork(1)
@State(Scope.Benchmark)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Warmup(iterations = 2, time = 1, timeUnit = TimeUnit.SECONDS)
@Measurement(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
public class PowBenchmark {

	private double i = 437.0;

	@Benchmark
	public double cross2() {
		return i * i;
	}

	@Benchmark
	public double pow2() {
		return Math.pow(i, 2);
	}

	@Benchmark
	public double cross3() {
		return i * i * i;
	}

	@Benchmark
	public double pow3() {
		return Math.pow(i, 3);
	}

	@Benchmark
	public double cross4() {
		return i * i * i * i;
	}

	@Benchmark
	public double pow4() {
		return Math.pow(i, 4);
	}

	@Benchmark
	public double cross5() {
		return i * i * i * i * i;
	}

	@Benchmark
	public double pow5() {
		return Math.pow(i, 5);
	}

	public static void main(String[] args) throws RunnerException {
		Options opt = new OptionsBuilder().include(".*" + PowBenchmark.class.getSimpleName() + ".*")
				.build();

		new Runner(opt).run();
	}

}