/** @see BigInteger#doubleValue() */
protected internal static double bigInteger2Double(BigInteger val)
{
// val.bitLength() < 64
if ((val.numberLength < 2) ||
((val.numberLength == 2) && (val.digits[1] > 0)))
{
return(val.longValue());
}
// val.bitLength() >= 33 * 32 > 1024
if (val.numberLength > 32)
{
return((val.sign > 0) ? java.lang.Double.POSITIVE_INFINITY
: java.lang.Double.NEGATIVE_INFINITY);
}
int bitLen = val.abs().bitLength();
long exponent = bitLen - 1;
int delta = bitLen - 54;
// We need 54 top bits from this, the 53th bit is always 1 in lVal.
long lVal = val.abs().shiftRight(delta).longValue();
/*
* Take 53 bits from lVal to mantissa. The least significant bit is
* needed for rounding.
*/
long mantissa = lVal & 0x1FFFFFFFFFFFFFL;
if (exponent == 1023)
{
if (mantissa == 0X1FFFFFFFFFFFFFL)
{
return((val.sign > 0) ? java.lang.Double.POSITIVE_INFINITY
: java.lang.Double.NEGATIVE_INFINITY);
}
if (mantissa == 0x1FFFFFFFFFFFFEL)
{
return((val.sign > 0) ? java.lang.Double.MAX_VALUE : -java.lang.Double.MAX_VALUE);
}
}
// Round the mantissa
if (((mantissa & 1) == 1) &&
(((mantissa & 2) == 2) || BitLevel.nonZeroDroppedBits(delta,
val.digits)))
{
mantissa += 2;
}
mantissa >>= 1; // drop the rounding bit
long resSign = (long)((val.sign < 0) ? 0x8000000000000000L : 0);
exponent = ((1023 + exponent) << 52) & 0x7FF0000000000000L;
long result = resSign | exponent | mantissa;
return(java.lang.Double.longBitsToDouble(result));
}
/** @see BigInteger#doubleValue() */
protected internal static double bigInteger2Double(BigInteger val)
{
// val.bitLength() < 64
if ((val.numberLength < 2)
|| ((val.numberLength == 2) && (val.digits[1] > 0))) {
return val.longValue();
}
// val.bitLength() >= 33 * 32 > 1024
if (val.numberLength > 32) {
return ((val.sign > 0) ? java.lang.Double.POSITIVE_INFINITY
: java.lang.Double.NEGATIVE_INFINITY);
}
int bitLen = val.abs().bitLength();
long exponent = bitLen - 1;
int delta = bitLen - 54;
// We need 54 top bits from this, the 53th bit is always 1 in lVal.
long lVal = val.abs().shiftRight(delta).longValue();
/*
* Take 53 bits from lVal to mantissa. The least significant bit is
* needed for rounding.
*/
long mantissa = lVal & 0x1FFFFFFFFFFFFFL;
if (exponent == 1023) {
if (mantissa == 0X1FFFFFFFFFFFFFL) {
return ((val.sign > 0) ? java.lang.Double.POSITIVE_INFINITY
: java.lang.Double.NEGATIVE_INFINITY);
}
if (mantissa == 0x1FFFFFFFFFFFFEL) {
return ((val.sign > 0) ? java.lang.Double.MAX_VALUE : -java.lang.Double.MAX_VALUE);
}
}
// Round the mantissa
if (((mantissa & 1) == 1)
&& (((mantissa & 2) == 2) || BitLevel.nonZeroDroppedBits(delta,
val.digits))) {
mantissa += 2;
}
mantissa >>= 1; // drop the rounding bit
long resSign = (long) ((val.sign < 0) ? 0x8000000000000000L : 0);
exponent = ((1023 + exponent) << 52) & 0x7FF0000000000000L;
long result = resSign | exponent | mantissa;
return java.lang.Double.longBitsToDouble(result);
}
public void TestAbs()
{
BigInteger bi;
int val;
Random rand = new Random();
for (int i = 0; i < 100; i++)
{
val = rand.Next(Int32.MinValue, Int32.MaxValue);
bi = new BigInteger(val);
Assert.AreEqual(Math.Abs(val), bi.abs());
}
bi = new BigInteger("4809238490238509385094809584086094850909458309580485093485093485094809580945809458340324342343242342343242", 10);
Assert.AreEqual("4809238490238509385094809584086094850909458309580485093485093485094809580945809458340324342343242342343242", bi.abs().ToString());
bi = new BigInteger();
Assert.AreEqual(0, bi.abs());
bi = new BigInteger("-38265236482749823794237948792386482364236462846234623862368236423764236624762384762384623862376482364823", 10);
Assert.AreEqual("38265236482749823794237948792386482364236462846234623862368236423764236624762384762384623862376482364823", bi.abs().ToString());
}
// secret shares an input based on n,r parameters
public SharedData[] ShareData(long secret)
{
BigInteger[] coefficients = new BigInteger[numNecessaryParts - 1];
BigInteger[] toReturn_p = new BigInteger[numAllParts];
for (int i = 0; i < numNecessaryParts - 1; i++)
{
BigInteger a = new BigInteger();
a.genRandomBits(64, new Random());
a = a.abs() % modP;
coefficients[i] = a;
}
for (long i = 0; i < numAllParts; i++)
{
toReturn_p[i] = 0;
for (long j = 0; j < numNecessaryParts - 1; j++)
{
BigInteger tmp = new BigInteger((long)(Math.Pow(i + 1, j + 1)));
toReturn_p[i] = (toReturn_p[i] + (BigInteger)(coefficients[j] * tmp)) % modP;
}
}
SharedData[] toReturn = new SharedData[numAllParts];
for (int i = 0; i < numAllParts; i++)
{
toReturn_p[i] = (toReturn_p[i] + new BigInteger(secret)) % modP;
toReturn[i].yi = toReturn_p[i].LongValue();
toReturn[i].xi = i + 1;
}
return(toReturn);
}
/** @see BigInteger#toString(int) */
protected internal static String bigInteger2String(BigInteger val, int radix)
{
int sign = val.sign;
int numberLength = val.numberLength;
int [] digits = val.digits;
if (sign == 0)
{
return("0"); //$NON-NLS-1$
}
if (numberLength == 1)
{
int highDigit = digits[numberLength - 1];
long v = highDigit & 0xFFFFFFFFL;
if (sign < 0)
{
v = -v;
}
return(java.lang.Long.toString(v, radix));
}
if ((radix == 10) || (radix < java.lang.Character.MIN_RADIX) ||
(radix > java.lang.Character.MAX_RADIX))
{
return(val.toString());
}
double bitsForRadixDigit;
bitsForRadixDigit = java.lang.Math.log(radix) / java.lang.Math.log(2);
int resLengthInChars = (int)(val.abs().bitLength() / bitsForRadixDigit + ((sign < 0) ? 1
: 0)) + 1;
char [] result = new char[resLengthInChars];
int currentChar = resLengthInChars;
int resDigit;
if (radix != 16)
{
int [] temp = new int[numberLength];
java.lang.SystemJ.arraycopy(digits, 0, temp, 0, numberLength);
int tempLen = numberLength;
int charsPerInt = digitFitInInt[radix];
int i;
// get the maximal power of radix that fits in int
int bigRadix = bigRadices[radix - 2];
while (true)
{
// divide the array of digits by bigRadix and convert remainders
// to characters collecting them in the char array
resDigit = Division.divideArrayByInt(temp, temp, tempLen,
bigRadix);
int previous = currentChar;
do
{
result[--currentChar] = java.lang.Character.forDigit(
resDigit % radix, radix);
} while (((resDigit /= radix) != 0) && (currentChar != 0));
int delta = charsPerInt - previous + currentChar;
for (i = 0; i < delta && currentChar > 0; i++)
{
result[--currentChar] = '0';
}
for (i = tempLen - 1; (i > 0) && (temp[i] == 0); i--)
{
;
}
tempLen = i + 1;
if ((tempLen == 1) && (temp[0] == 0)) // the quotient is 0
{
break;
}
}
}
else
{
// radix == 16
for (int i = 0; i < numberLength; i++)
{
for (int j = 0; (j < 8) && (currentChar > 0); j++)
{
resDigit = digits[i] >> (j << 2) & 0xf;
result[--currentChar] = java.lang.Character.forDigit(resDigit, 16);
}
}
}
while (result[currentChar] == '0')
{
currentChar++;
}
if (sign == -1)
{
result[--currentChar] = '-';
}
return(new String(result, currentChar, resLengthInChars - currentChar));
}
/** @see BigInteger#toString(int) */
protected internal static String bigInteger2String(BigInteger val, int radix)
{
int sign = val.sign;
int numberLength = val.numberLength;
int []digits = val.digits;
if (sign == 0) {
return "0"; //$NON-NLS-1$
}
if (numberLength == 1) {
int highDigit = digits[numberLength - 1];
long v = highDigit & 0xFFFFFFFFL;
if (sign < 0) {
v = -v;
}
return java.lang.Long.toString(v, radix);
}
if ((radix == 10) || (radix < java.lang.Character.MIN_RADIX)
|| (radix > java.lang.Character.MAX_RADIX)) {
return val.toString();
}
double bitsForRadixDigit;
bitsForRadixDigit = java.lang.Math.log(radix) / java.lang.Math.log(2);
int resLengthInChars = (int) (val.abs().bitLength() / bitsForRadixDigit + ((sign < 0) ? 1
: 0)) + 1;
char []result = new char[resLengthInChars];
int currentChar = resLengthInChars;
int resDigit;
if (radix != 16) {
int []temp = new int[numberLength];
java.lang.SystemJ.arraycopy(digits, 0, temp, 0, numberLength);
int tempLen = numberLength;
int charsPerInt = digitFitInInt[radix];
int i;
// get the maximal power of radix that fits in int
int bigRadix = bigRadices[radix - 2];
while (true) {
// divide the array of digits by bigRadix and convert remainders
// to characters collecting them in the char array
resDigit = Division.divideArrayByInt(temp, temp, tempLen,
bigRadix);
int previous = currentChar;
do {
result[--currentChar] = java.lang.Character.forDigit(
resDigit % radix, radix);
} while (((resDigit /= radix) != 0) && (currentChar != 0));
int delta = charsPerInt - previous + currentChar;
for (i = 0; i < delta && currentChar > 0; i++) {
result[--currentChar] = '0';
}
for (i = tempLen - 1; (i > 0) && (temp[i] == 0); i--) {
;
}
tempLen = i + 1;
if ((tempLen == 1) && (temp[0] == 0)) { // the quotient is 0
break;
}
}
} else {
// radix == 16
for (int i = 0; i < numberLength; i++) {
for (int j = 0; (j < 8) && (currentChar > 0); j++) {
resDigit = digits[i] >> (j << 2) & 0xf;
result[--currentChar] = java.lang.Character.forDigit(resDigit, 16);
}
}
}
while (result[currentChar] == '0') {
currentChar++;
}
if (sign == -1) {
result[--currentChar] = '-';
}
return new String(result, currentChar, resLengthInChars - currentChar);
}
// secret shares an input based on n,r parameters
public SharedData[] ShareData( long secret)
{
BigInteger[] coefficients = new BigInteger[numNecessaryParts - 1];
BigInteger[] toReturn_p = new BigInteger[numAllParts];
for (int i = 0; i < numNecessaryParts - 1; i++)
{
BigInteger a = new BigInteger();
a.genRandomBits(64, new Random());
a = a.abs() % modP;
coefficients[i] = a;
}
for (long i = 0; i < numAllParts; i++)
{
toReturn_p[i] = 0;
for (long j = 0; j < numNecessaryParts - 1; j++)
{
BigInteger tmp = new BigInteger((long)(Math.Pow(i + 1, j + 1)));
toReturn_p[i] = (toReturn_p[i] + (BigInteger)(coefficients[j] * tmp)) % modP;
}
}
SharedData[] toReturn = new SharedData[numAllParts];
for (int i = 0; i < numAllParts; i++)
{
toReturn_p[i] = (toReturn_p[i] + new BigInteger(secret)) % modP;
toReturn[i].yi = toReturn_p[i].LongValue();
toReturn[i].xi = i + 1;
}
return toReturn;
}
