Value GranularityRounderPreferredNumbers::roundDown(Value value) {
uassertNonNegativeNumber(value);
if (value.coerceToDouble() == 0.0) {
return value;
}
if (value.getType() == BSONType::NumberDecimal) {
Decimal128 number = value.getDecimal();
Decimal128 multiplier = Decimal128(1);
// '_baseSeries' contains doubles, so we create a vector that contains the Decimal128
// versions of the numbers in '_baseSeries' to make it easier to compare values to 'number'.
vector<Decimal128> decimalSeries;
for (auto&& doubleNumber : _baseSeries) {
decimalSeries.push_back(Decimal128(doubleNumber));
}
while (number.isLessEqual(decimalSeries.front().multiply(multiplier))) {
multiplier = multiplier.divide(Decimal128(10));
}
Decimal128 previousMax;
while (number.isGreater(decimalSeries.back().multiply(multiplier))) {
previousMax = decimalSeries.back().multiply(multiplier);
multiplier = multiplier.multiply(Decimal128(10));
if (number.isLessEqual(decimalSeries.front().multiply(multiplier))) {
// The number is less than or equal to the current min, so it must round down to the
// previous max. For example, rounding down 0.8 in the E6 series.
return Value(previousMax);
}
}
// After scaling up or down, 'number' should now fall into the range spanned by
// decimalSeries[i] * multiplier for all i in decimalSeries.
invariant(number.isGreater(decimalSeries.front().multiply(multiplier)) &&
number.isLessEqual(decimalSeries.back().multiply(multiplier)));
// Get an iterator pointing to the first element in '_baseSeries' that is greater than or
// equal to 'number'.
auto iterator =
std::lower_bound(decimalSeries.begin(),
decimalSeries.end(),
number,
[multiplier](Decimal128 seriesNumber, Decimal128 roundingNumber) {
return seriesNumber.multiply(multiplier).isLess(roundingNumber);
});
// We need to move the iterator back by one so that we round down to a number that is
// strictly less than the value we are rounding.
return Value(Value((*(iterator - 1)).multiply(multiplier)));
} else {
double number = value.coerceToDouble();
double multiplier = 1.0;
while (number <= (_baseSeries.front() * multiplier)) {
multiplier /= 10.0;
}
double previousMax;
while (number > (_baseSeries.back() * multiplier)) {
previousMax = _baseSeries.back() * multiplier;
multiplier *= 10.0;
if (number <= _baseSeries.front() * multiplier) {
// The number is less than or equal to the current min, so it must round down to the
// previous max. For example, rounding down 0.8 in the E6 series.
return Value(previousMax);
}
}
// After scaling up or down, 'number' should now fall into the range spanned by
// _baseSeries[i] * multiplier for all i in _baseSeries.
invariant(number > (_baseSeries.front() * multiplier) &&
number <= (_baseSeries.back() * multiplier));
// Get an iterator pointing to the first element in '_baseSeries' that is greater than or
// equal to 'number'.
auto iterator = std::lower_bound(_baseSeries.begin(),
_baseSeries.end(),
number,
[multiplier](double seriesNumber, double roundingNumber) {
return (seriesNumber * multiplier) < roundingNumber;
});
// We need to move the iterator back by one so that we round down to a number that is
// strictly less than the value we are rounding.
return Value(Value(*(iterator - 1) * multiplier));
}
}
Value GranularityRounderPreferredNumbers::roundUp(Value value) {
uassertNonNegativeNumber(value);
if (value.coerceToDouble() == 0.0) {
return value;
}
if (value.getType() == BSONType::NumberDecimal) {
Decimal128 number = value.getDecimal();
Decimal128 multiplier = Decimal128(1);
// '_baseSeries' contains doubles, so we create a vector that contains the Decimal128
// versions of the numbers in '_baseSeries' to make it easier to compare values to 'number'.
vector<Decimal128> decimalSeries;
for (auto&& doubleNumber : _baseSeries) {
decimalSeries.push_back(Decimal128(doubleNumber));
}
while (number.isGreaterEqual(decimalSeries.back().multiply(multiplier))) {
multiplier = multiplier.multiply(Decimal128(10));
}
Decimal128 previousMin;
while (number.isLess(decimalSeries.front().multiply(multiplier))) {
previousMin = decimalSeries.front().multiply(multiplier);
multiplier = multiplier.divide(Decimal128(10));
if (number.isGreaterEqual(decimalSeries.back().multiply(multiplier))) {
// The number was between the previous min and the current max, so it must round up
// to the previous min. For example, rounding up 0.8 in the E6 series.
return Value(previousMin);
}
}
// After scaling up or down, 'number' should now fall into the range spanned by
// decimalSeries[i] * multiplier for all i in decimalSeries.
invariant(number.isGreaterEqual(decimalSeries.front().multiply(multiplier)) &&
number.isLess(decimalSeries.back().multiply(multiplier)));
// Get an iterator pointing to the first element in '_baseSeries' that is greater
// than'number'.
auto iterator =
std::upper_bound(decimalSeries.begin(),
decimalSeries.end(),
number,
[multiplier](Decimal128 roundingNumber, Decimal128 seriesNumber) {
return roundingNumber.isLess(seriesNumber.multiply(multiplier));
});
return Value((*iterator).multiply(multiplier));
} else {
double number = value.coerceToDouble();
double multiplier = 1.0;
while (number >= (_baseSeries.back() * multiplier)) {
multiplier *= 10.0;
}
double previousMin;
while (number < (_baseSeries.front() * multiplier)) {
previousMin = _baseSeries.front() * multiplier;
multiplier /= 10.0;
if (number >= (_baseSeries.back() * multiplier)) {
// The number was between the previous min and the current max, so it must round up
// to the previous min. For example, rounding up 0.8 in the E6 series.
return Value(previousMin);
}
}
// After scaling up or down, 'number' should now fall into the range spanned by
// _baseSeries[i] * multiplier for all i in _baseSeries.
invariant(number >= (_baseSeries.front() * multiplier) &&
number < (_baseSeries.back() * multiplier));
// Get an iterator pointing to the first element in '_baseSeries' that is greater
// than'number'.
auto iterator = std::upper_bound(_baseSeries.begin(),
_baseSeries.end(),
number,
[multiplier](double roundingNumber, double seriesNumber) {
return roundingNumber < (seriesNumber * multiplier);
});
return Value(*iterator * multiplier);
}
}