Java BigInteger Value Check isPowerOfTwo(BigInteger x)

Description

is Power Of Two

License

Open Source License

Declaration

public static boolean isPowerOfTwo(BigInteger x) 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

import java.math.BigInteger;

public class Main {
    public static boolean isPowerOfTwo(BigInteger x) {
        return x.signum() > 0 && x.getLowestSetBit() == x.bitLength() - 1;
    }//from  ww w . ja v a 2s.  co m

    /**
     * Returns {@code true} if {@code x} represents a power of two.
     *
     * <p>This differs from {@code Integer.bitCount(x) == 1}, because
     * {@code Integer.bitCount(Integer.MIN_VALUE) == 1}, but {@link Integer#MIN_VALUE} is not a power
     * of two.
     */
    public static boolean isPowerOfTwo(int x) {
        return x > 0 & (x & (x - 1)) == 0;
    }
}

Related

1. isOdd(BigInteger in)
2. isOdd(BigInteger x)
3. isPerfectCubic(BigInteger n)
4. isPositive(final BigInteger value)
5. isPowerOfTwo(BigInteger bintValue)
6. isRootInQuadraticResidues(BigInteger n, BigInteger p)
7. isSqrtXXX(BigInteger n, BigInteger root)
8. isZero(BigInteger value)