Example usage for java.math BigInteger multiply

Introduction

In this page you can find the example usage for java.math BigInteger multiply.

Prototype

BigInteger multiply(long v)

Source Link

Document

Package private methods used by BigDecimal code to multiply a BigInteger with a long.

Usage

From source file:Main.java

public static BigInteger pow(BigInteger base, BigInteger exponent) {
    BigInteger result = BigInteger.ONE;
    while (exponent.signum() > 0) {
        if (exponent.testBit(0))
            result = result.multiply(base);
        base = base.multiply(base);//from w  ww . j av  a  2  s  .  c o  m
        exponent = exponent.shiftRight(1);
    }
    return result;
}

From source file:Main.java

public static BigInteger hashFnv1A(byte[] data) {
    final BigInteger INIT64 = new BigInteger("cbf29ce484222325", 16);
    final BigInteger PRIME64 = new BigInteger("100000001b3", 16);
    final BigInteger MOD64 = new BigInteger("2").pow(64);

    BigInteger hash = INIT64;

    for (byte b : data) {
        hash = hash.xor(BigInteger.valueOf((int) b & 0xff));
        hash = hash.multiply(PRIME64).mod(MOD64);
    }/*from   w  w w .j  av a  2 s  .  c  o  m*/

    return hash;
}

From source file:edu.hku.sdb.udf.util.UDFHandler.java

/**
 * Calculates the ciphertext ce according to updated p, q values during A's keyUpdate operation.
 *
 * @param a the ciphertext of A, whose value < n
 * @param s the ciphertext of helper S, whose value < n
 * @param p the new p generated in A's keyUpdate operation
 * @param q the new q generated in A's keyUpdate operation
 * @param n//  w w w . ja v  a2 s.  c o m
 * @return
 */
public static BigInteger keyUpdate(BigInteger a, BigInteger s, BigInteger p, BigInteger q, BigInteger n) {

    BigInteger sp = s.modPow(p, n);
    return (q.multiply(a).multiply(sp)).mod(n);
}

From source file:edu.hku.sdb.udf.util.UDFHandler.java

/**
 * Returns (ae * be) mod n according to SDB Multiplication (EE Mode) protocol
 *
 * @param multiplicand ae, whose value < n
 * @param multiplier   be, whose value < n
 * @param n/* w  ww. j  a  v a 2s . c o m*/
 * @return
 */
public static BigInteger multi(BigInteger multiplicand, BigInteger multiplier, BigInteger n) {
    BigInteger result = (multiplicand.multiply(multiplier)).mod(n);
    return result;
}

From source file:Main.java

public static BigInteger getZ(ArrayList<byte[]> c1, ArrayList<byte[]> c2, BigInteger p) {
    BigInteger z = BigInteger.ZERO;

    //TODO: make sure c1 and c2 are of the same size
    int size = c1.size();
    if (size > c2.size()) {
        size = c2.size();//from  w w  w .j a  v  a2s.  c  o  m
    }

    for (int i = 0; i < size; i++) {
        BigInteger c1BI = new BigInteger(1, c1.get(i));
        BigInteger c2BI = new BigInteger(1, c2.get(i));
        BigInteger exp = new BigInteger(1, ByteBuffer.allocate(8).putLong((long) Math.pow(2, i)).array());

        z = z.add((c1BI.multiply(c2BI)).modPow(exp, p));
        Log.d("CeCk", "z calculation " + i + "/" + size + " round");
    }
    return z.mod(p);
}

From source file:org.apache.hadoop.hbase.manual.utils.HBaseUtils.java

/**
 * Splits the given BigInteger into numberOfSplits parts
 * @param maxValue//from w ww  .java 2  s .  c  o  m
 * @param numberOfSplits
 * @return array of BigInteger which is of size (numberOfSplits-1)
 */
private static BigInteger[] split(BigInteger maxValue, int numberOfSplits) {
    BigInteger[] splits = new BigInteger[numberOfSplits - 1];
    BigInteger sizeOfEachSplit = maxValue.divide(BigInteger.valueOf(numberOfSplits));
    for (int i = 1; i < numberOfSplits; i++) {
        splits[i - 1] = sizeOfEachSplit.multiply(BigInteger.valueOf(i));
    }
    return splits;
}

From source file:cc.redberry.core.number.Exponentiation.java

public static Complex findIntegerRoot(Complex base, BigInteger power) {
    BigInteger rDenominator = ((Rational) base.getReal()).getDenominator();
    BigInteger iDenominator = ((Rational) base.getImaginary()).getDenominator();

    BigInteger lcm = rDenominator.gcd(iDenominator);
    lcm = rDenominator.divide(lcm);//from www.  j  av a  2s .  co m
    lcm = lcm.multiply(iDenominator);

    BigInteger lcmRoot = findIntegerRoot(lcm, power);

    if (lcm == null)
        return null;

    base = base.multiply(lcm);

    Complex numericValue = base.pow(1.0 / power.doubleValue());
    double real = numericValue.getReal().doubleValue();
    double imaginary = numericValue.getImaginary().doubleValue();

    int ceilReal = (int) Math.ceil(real), floorReal = (int) Math.floor(real),
            ceilImaginary = (int) Math.ceil(imaginary), floorImaginary = (int) Math.floor(imaginary);

    Complex candidate;
    if ((candidate = new Complex(ceilReal, ceilImaginary)).pow(power).equals(base))
        return candidate.divide(lcmRoot);
    if ((candidate = new Complex(floorReal, ceilImaginary)).pow(power).equals(base))
        return candidate.divide(lcmRoot);
    if ((candidate = new Complex(ceilReal, floorImaginary)).pow(power).equals(base))
        return candidate.divide(lcmRoot);
    if ((candidate = new Complex(floorReal, floorImaginary)).pow(power).equals(base))
        return candidate.divide(lcmRoot);
    return null;
}

From source file:edu.utah.further.core.api.math.ArithmeticUtil.java

/**
 * Compute the factorial of a {@link BigInteger}. Allows computing big numbers.
 *
 * @param n/*from   w  w  w.  j a  va  2s. com*/
 * @return
 */
public static BigInteger factorial(final int n) {
    BigInteger fact = BigInteger.ONE;
    for (int i = n; i > 1; i--) {
        fact = fact.multiply(new BigInteger(Integer.toString(i)));
    }
    return fact;
}

From source file:gedi.util.math.stat.distributions.OccupancyNumberDistribution.java

private static final BigInteger factorial(int b) {
    if (b == 0)/*from   ww w. j  a v  a  2  s. co m*/
        return BigInteger.ONE;
    BigInteger re = BigInteger.valueOf(b);
    for (int i = b - 1; i > 1; i--)
        re = re.multiply(BigInteger.valueOf(i));
    return re;
}

From source file:gedi.util.math.stat.distributions.OccupancyNumberDistribution.java

private static final BigInteger factorial(int b, int k) {
    if (b == 0 || k == 0)
        return BigInteger.ONE;
    BigInteger re = BigInteger.valueOf(b);
    for (int i = b - 1; i > b - k; i--)
        re = re.multiply(BigInteger.valueOf(i));
    return re;/*  w ww . ja va  2  s .  co  m*/
}