diff options
Diffstat (limited to 'src/mongo/platform/decimal128.cpp')
| -rw-r--r-- | src/mongo/platform/decimal128.cpp | 23 |
1 files changed, 10 insertions, 13 deletions
diff --git a/src/mongo/platform/decimal128.cpp b/src/mongo/platform/decimal128.cpp index 0d12479f70a..ef785025b17 100644 --- a/src/mongo/platform/decimal128.cpp +++ b/src/mongo/platform/decimal128.cpp @@ -827,36 +827,33 @@ Decimal128 Decimal128::exponential(std::uint32_t* signalingFlags, RoundingMode r return Decimal128{libraryTypeToValue(current)}; } -Decimal128 Decimal128::logarithm(RoundingMode roundMode) const { +Decimal128 Decimal128::naturalLogarithm(RoundingMode roundMode) const { std::uint32_t throwAwayFlag = 0; - return logarithm(&throwAwayFlag, roundMode); + return naturalLogarithm(&throwAwayFlag, roundMode); } -Decimal128 Decimal128::logarithm(std::uint32_t* signalingFlags, RoundingMode roundMode) const { +Decimal128 Decimal128::naturalLogarithm(std::uint32_t* signalingFlags, + RoundingMode roundMode) const { BID_UINT128 current = decimal128ToLibraryType(_value); current = bid128_log(current, roundMode, signalingFlags); return Decimal128{libraryTypeToValue(current)}; } -Decimal128 Decimal128::logarithm(const Decimal128& other, RoundingMode roundMode) const { +Decimal128 Decimal128::logarithm(const Decimal128& base, RoundingMode roundMode) const { std::uint32_t throwAwayFlag = 0; - if (other.isEqual(Decimal128(2))) { + if (base.isEqual(Decimal128(2))) { BID_UINT128 current = decimal128ToLibraryType(_value); current = bid128_log2(current, roundMode, &throwAwayFlag); return Decimal128{libraryTypeToValue(current)}; } - if (other.isEqual(Decimal128(10))) { + if (base.isEqual(Decimal128(10))) { BID_UINT128 current = decimal128ToLibraryType(_value); current = bid128_log10(current, roundMode, &throwAwayFlag); return Decimal128{libraryTypeToValue(current)}; } - return logarithm(other, &throwAwayFlag); -} - -Decimal128 Decimal128::logarithm(const Decimal128& other, - std::uint32_t* signalingFlags, - RoundingMode roundMode) const { - return logarithm(signalingFlags, roundMode).divide(other); + // Logarithm with a generic base is equivalent to `ln(input) / ln(base)`. + return naturalLogarithm(&throwAwayFlag, roundMode) + .divide(base.naturalLogarithm(&throwAwayFlag, roundMode)); } Decimal128 Decimal128::modulo(const Decimal128& other) const { |
