/**
* Set the digit list to a representation of the given double value.
* This method supports both fixed-point and exponential notation.
* @param source Value to be converted.
*/
void
DigitList::set(double source)
{
// for now, simple implementation; later, do proper IEEE stuff
char rep[MAX_DIGITS + 8]; // Extra space for '+', '.', e+NNN, and '\0' (actually +8 is enough)
// Generate a representation of the form /[+-][0-9]+e[+-][0-9]+/
sprintf(rep, "%+1.*e", MAX_DBL_DIGITS - 1, source);
U_ASSERT(uprv_strlen(rep) < sizeof(rep));
// uprv_decNumberFromString() will parse the string expecting '.' as a
// decimal separator, however sprintf() can use ',' in certain locales.
// Overwrite a different decimal separator with '.' here before proceeding.
loadDecimalChar();
if (gDecimal != '.') {
char *decimalPt = strchr(rep, gDecimal);
if (decimalPt != NULL) {
*decimalPt = '.';
}
}
// Create a decNumber from the string.
uprv_decNumberFromString(fDecNumber, rep, &fContext);
uprv_decNumberTrim(fDecNumber);
fDouble = source;
fHaveDouble = TRUE;
}
/**
* Set the digit list to a representation of the given double value.
* This method supports both fixed-point and exponential notation.
* @param source Value to be converted.
*/
void
DigitList::set(double source)
{
// for now, simple implementation; later, do proper IEEE stuff
char rep[MAX_DIGITS + 8]; // Extra space for '+', '.', e+NNN, and '\0' (actually +8 is enough)
// Generate a representation of the form /[+-][0-9].[0-9]+e[+-][0-9]+/
// Can also generate /[+-]nan/ or /[+-]inf/
// TODO: Use something other than sprintf() here, since it's behavior is somewhat platform specific.
// That is why infinity is special cased here.
if (uprv_isInfinite(source)) {
if (uprv_isNegativeInfinity(source)) {
uprv_strcpy(rep,"-inf"); // Handle negative infinity
} else {
uprv_strcpy(rep,"inf");
}
} else {
sprintf(rep, "%+1.*e", MAX_DBL_DIGITS - 1, source);
}
U_ASSERT(uprv_strlen(rep) < sizeof(rep));
// uprv_decNumberFromString() will parse the string expecting '.' as a
// decimal separator, however sprintf() can use ',' in certain locales.
// Overwrite a ',' with '.' here before proceeding.
char *decimalSeparator = strchr(rep, ',');
if (decimalSeparator != NULL) {
*decimalSeparator = '.';
}
// Create a decNumber from the string.
uprv_decNumberFromString(fDecNumber, rep, &fContext);
uprv_decNumberTrim(fDecNumber);
internalSetDouble(source);
}
void
DigitList::round(int32_t maximumDigits)
{
int32_t savedDigits = fContext.digits;
fContext.digits = maximumDigits;
uprv_decNumberPlus(fDecNumber, fDecNumber, &fContext);
fContext.digits = savedDigits;
uprv_decNumberTrim(fDecNumber);
fHaveDouble = FALSE;
}
/**
* Round the representation to the given number of digits.
* @param maximumDigits The maximum number of digits to be shown.
* Upon return, count will be less than or equal to maximumDigits.
*/
void
DigitList::round(int32_t maximumDigits)
{
int32_t savedDigits = fContext.digits;
fContext.digits = maximumDigits;
uprv_decNumberPlus(fDecNumber, fDecNumber, &fContext);
fContext.digits = savedDigits;
uprv_decNumberTrim(fDecNumber);
internalClear();
}
/**
* Round the representation to the given number of digits.
* @param maximumDigits The maximum number of digits to be shown.
* Upon return, count will be less than or equal to maximumDigits.
*/
void
DigitList::round(int32_t maximumDigits)
{
reduce();
if (maximumDigits >= fDecNumber->digits) {
return;
}
int32_t savedDigits = fContext.digits;
fContext.digits = maximumDigits;
uprv_decNumberPlus(fDecNumber, fDecNumber, &fContext);
fContext.digits = savedDigits;
uprv_decNumberTrim(fDecNumber);
reduce();
internalClear();
}
void
DigitList::set(double source)
{
// for now, simple implementation; later, do proper IEEE stuff
char rep[MAX_DIGITS + 8]; // Extra space for '+', '.', e+NNN, and '\0' (actually +8 is enough)
// Generate a representation of the form /[+-][0-9]+e[+-][0-9]+/
sprintf(rep, "%+1.*e", MAX_DBL_DIGITS - 1, source);
U_ASSERT(uprv_strlen(rep) < sizeof(rep));
// Create a decNumber from the string.
uprv_decNumberFromString(fDecNumber, rep, &fContext);
uprv_decNumberTrim(fDecNumber);
fDouble = source;
fHaveDouble = TRUE;
}
/**
* Return true if the number represented by this object can fit into
* a long.
*/
UBool
DigitList::fitsIntoInt64(UBool ignoreNegativeZero) /*const*/
{
if (decNumberIsSpecial(this->fDecNumber)) {
// NaN or Infinity. Does not fit in int32.
return FALSE;
}
uprv_decNumberTrim(this->fDecNumber);
if (fDecNumber->exponent < 0) {
// Number contains fraction digits.
return FALSE;
}
if (decNumberIsZero(this->fDecNumber) && !ignoreNegativeZero &&
(fDecNumber->bits & DECNEG) != 0) {
// Negative Zero, not ingored. Cannot represent as a long.
return FALSE;
}
if (getUpperExponent() < 19) {
// The number is 18 or fewer digits.
// The max and min int64 are 19 digts, so this number fits.
// This is the common case.
return TRUE;
}
// TODO: Should cache these constants; construction is relatively costly.
// But not of huge consequence; they're only needed for 19 digit ints.
UErrorCode status = U_ZERO_ERROR;
DigitList min64; min64.set("-9223372036854775808", status);
if (this->compare(min64) < 0) {
return FALSE;
}
DigitList max64; max64.set("9223372036854775807", status);
if (this->compare(max64) > 0) {
return FALSE;
}
if (U_FAILURE(status)) {
return FALSE;
}
return true;
}
// -------------------------------------
// trim - remove trailing fraction zero digits.
void
DigitList::trim() {
uprv_decNumberTrim(fDecNumber);
}
