// Like GetBitCount(Abs(x)), except 0 maps to 0
public static int BitLength(BigInteger x) {
if (x.IsZero()) {
return 0;
}
return x.Abs().GetBitCount();
}
/// <summary>
/// Test for shift overflow on negative BigIntegers
/// </summary>
/// <param name="self">Value before shifting</param>
/// <param name="result">Value after shifting</param>
/// <returns>-1 if we overflowed, otherwise result</returns>
/// <remarks>
/// Negative Bignums are supposed to look like they are stored in 2s complement infinite bit string,
/// a negative number should always have spare 1s available for on the left hand side for right shifting.
/// E.g. 8 == ...0001000; -8 == ...1110111, where the ... means that the left hand value is repeated indefinitely.
/// The test here checks whether we have overflowed into the infinite 1s.
/// [Arguably this should get factored into the BigInteger class.]
/// </remarks>
private static BigInteger/*!*/ ShiftOverflowCheck(BigInteger/*!*/ self, BigInteger/*!*/ result) {
if (self.IsNegative() && result.IsZero()) {
return -1;
}
return result;
}
/*!*/
private static BigInteger SignedGcd(BigInteger/*!*/ a, BigInteger/*!*/ b)
{
while (!b.IsZero()) {
BigInteger t = b;
b = a % b;
a = t;
}
return a;
}
private static string/*!*/ ToDigits(BigInteger/*!*/ val, int radix, bool lower) {
if (val.IsZero()) {
return "0";
}
StringBuilder str = new StringBuilder();
while (val != 0) {
int digit = (int)(val % radix);
if (digit < 10) str.Append((char)((digit) + '0'));
else if (lower) str.Append((char)((digit - 10) + 'a'));
else str.Append((char)((digit - 10) + 'A'));
val /= radix;
}
StringBuilder res = new StringBuilder(str.Length);
for (int i = str.Length - 1; i >= 0; i--) {
res.Append(str[i]);
}
return res.ToString();
}
public static string/*!*/ __format__(CodeContext/*!*/ context, BigInteger/*!*/ self, [NotNull]string/*!*/ formatSpec) {
StringFormatSpec spec = StringFormatSpec.FromString(formatSpec);
if (spec.Precision != null) {
throw PythonOps.ValueError("Precision not allowed in integer format specifier");
}
BigInteger val = self;
if (self < 0) {
val = -self;
}
string digits;
switch (spec.Type) {
case 'n':
CultureInfo culture = PythonContext.GetContext(context).NumericCulture;
if (culture == CultureInfo.InvariantCulture) {
// invariant culture maps to CPython's C culture, which doesn't
// include any formatting info.
goto case 'd';
}
digits = ToCultureString(val, PythonContext.GetContext(context).NumericCulture);
break;
case null:
case 'd':
digits = val.ToString();
break;
case '%':
if (val == BigInteger.Zero) {
digits = "0.000000%";
} else {
digits = val.ToString() + "00.000000%";
}
break;
case 'e': digits = ToExponent(val, true, 6, 7); break;
case 'E': digits = ToExponent(val, false, 6, 7); break;
case 'f':
if (val != BigInteger.Zero) {
digits = val.ToString() + ".000000";
} else {
digits = "0.000000";
}
break;
case 'F':
if (val != BigInteger.Zero) {
digits = val.ToString() + ".000000";
} else {
digits = "0.000000";
}
break;
case 'g':
if (val >= 1000000) {
digits = ToExponent(val, true, 0, 6);
} else {
digits = val.ToString();
}
break;
case 'G':
if (val >= 1000000) {
digits = ToExponent(val, false, 0, 6);
} else {
digits = val.ToString();
}
break;
case 'X':
digits = AbsToHex(val, false);
break;
case 'x':
digits = AbsToHex(val, true);
break;
case 'o': // octal
digits = ToOctal(val, true);
break;
case 'b': // binary
digits = ToBinary(val, false, true);
break;
case 'c': // single char
int iVal;
if (spec.Sign != null) {
throw PythonOps.ValueError("Sign not allowed with integer format specifier 'c'");
} else if (!self.AsInt32(out iVal)) {
throw PythonOps.OverflowError("long int too large to convert to int");
} else if(iVal < Char.MinValue || iVal > Char.MaxValue) {
throw PythonOps.OverflowError("%c arg not in range(0x10000)");
}
digits = Builtin.chr(iVal);
break;
default:
throw PythonOps.ValueError("Unknown format code '{0}'", spec.Type.ToString());
}
Debug.Assert(digits[0] != '-');
return spec.AlignNumericText(digits, self.IsZero(), self.IsPositive());
}
public static bool __nonzero__(BigInteger x) {
return !x.IsZero();
}
