| // © 2020 and later: Unicode, Inc. and others. |
| // License & terms of use: http://www.unicode.org/copyright.html |
| |
| #include "unicode/utypes.h" |
| |
| #if !UCONFIG_NO_FORMATTING |
| |
| #include <cmath> |
| |
| #include "cmemory.h" |
| #include "number_decimalquantity.h" |
| #include "number_roundingutils.h" |
| #include "uarrsort.h" |
| #include "uassert.h" |
| #include "unicode/fmtable.h" |
| #include "unicode/localpointer.h" |
| #include "unicode/measunit.h" |
| #include "unicode/measure.h" |
| #include "units_complexconverter.h" |
| #include "units_converter.h" |
| |
| U_NAMESPACE_BEGIN |
| namespace units { |
| |
| ComplexUnitsConverter::ComplexUnitsConverter(const MeasureUnitImpl &inputUnit, |
| const MeasureUnitImpl &outputUnits, |
| const ConversionRates &ratesInfo, UErrorCode &status) |
| : units_(outputUnits.extractIndividualUnits(status)) { |
| if (U_FAILURE(status)) { |
| return; |
| } |
| |
| U_ASSERT(units_.length() != 0); |
| |
| // Save the desired order of output units before we sort units_ |
| for (int32_t i = 0; i < units_.length(); i++) { |
| outputUnits_.emplaceBackAndCheckErrorCode(status, units_[i]->copy(status).build(status)); |
| } |
| |
| // NOTE: |
| // This comparator is used to sort the units in a descending order. Therefore, we return -1 if |
| // the left is bigger than right and so on. |
| auto descendingCompareUnits = [](const void *context, const void *left, const void *right) { |
| UErrorCode status = U_ZERO_ERROR; |
| |
| const auto *leftPointer = static_cast<const MeasureUnitImpl *const *>(left); |
| const auto *rightPointer = static_cast<const MeasureUnitImpl *const *>(right); |
| |
| UnitConverter fromLeftToRight(**leftPointer, // |
| **rightPointer, // |
| *static_cast<const ConversionRates *>(context), // |
| status); |
| |
| double rightFromOneLeft = fromLeftToRight.convert(1.0); |
| if (std::abs(rightFromOneLeft - 1.0) < 0.0000000001) { // Equals To |
| return 0; |
| } else if (rightFromOneLeft > 1.0) { // Greater Than |
| return -1; |
| } |
| |
| return 1; // Less Than |
| }; |
| |
| uprv_sortArray(units_.getAlias(), // |
| units_.length(), // |
| sizeof units_[0], /* NOTE: we have already asserted that the units_ is not empty.*/ // |
| descendingCompareUnits, // |
| &ratesInfo, // |
| false, // |
| &status // |
| ); |
| |
| // In case the `outputUnits` are `UMEASURE_UNIT_MIXED` such as `foot+inch`. In this case we need more |
| // converters to convert from the `inputUnit` to the first unit in the `outputUnits`. Then, a |
| // converter from the first unit in the `outputUnits` to the second unit and so on. |
| // For Example: |
| // - inputUnit is `meter` |
| // - outputUnits is `foot+inch` |
| // - Therefore, we need to have two converters: |
| // 1. a converter from `meter` to `foot` |
| // 2. a converter from `foot` to `inch` |
| // - Therefore, if the input is `2 meter`: |
| // 1. convert `meter` to `foot` --> 2 meter to 6.56168 feet |
| // 2. convert the residual of 6.56168 feet (0.56168) to inches, which will be (6.74016 |
| // inches) |
| // 3. then, the final result will be (6 feet and 6.74016 inches) |
| for (int i = 0, n = units_.length(); i < n; i++) { |
| if (i == 0) { // first element |
| unitConverters_.emplaceBackAndCheckErrorCode(status, inputUnit, *units_[i], ratesInfo, |
| status); |
| } else { |
| unitConverters_.emplaceBackAndCheckErrorCode(status, *units_[i - 1], *units_[i], ratesInfo, |
| status); |
| } |
| |
| if (U_FAILURE(status)) { |
| return; |
| } |
| } |
| } |
| |
| UBool ComplexUnitsConverter::greaterThanOrEqual(double quantity, double limit) const { |
| U_ASSERT(unitConverters_.length() > 0); |
| |
| // First converter converts to the biggest quantity. |
| double newQuantity = unitConverters_[0]->convert(quantity); |
| return newQuantity >= limit; |
| } |
| |
| MaybeStackVector<Measure> ComplexUnitsConverter::convert(double quantity, |
| icu::number::impl::RoundingImpl *rounder, |
| UErrorCode &status) const { |
| // TODO(hugovdm): return an error for "foot-and-foot"? |
| MaybeStackVector<Measure> result; |
| int sign = 1; |
| if (quantity < 0) { |
| quantity *= -1; |
| sign = -1; |
| } |
| |
| // For N converters: |
| // - the first converter converts from the input unit to the largest unit, |
| // - N-1 converters convert to bigger units for which we want integers, |
| // - the Nth converter (index N-1) converts to the smallest unit, for which |
| // we keep a double. |
| MaybeStackArray<int64_t, 5> intValues(unitConverters_.length() - 1, status); |
| if (U_FAILURE(status)) { |
| return result; |
| } |
| uprv_memset(intValues.getAlias(), 0, (unitConverters_.length() - 1) * sizeof(int64_t)); |
| |
| for (int i = 0, n = unitConverters_.length(); i < n; ++i) { |
| quantity = (*unitConverters_[i]).convert(quantity); |
| if (i < n - 1) { |
| // The double type has 15 decimal digits of precision. For choosing |
| // whether to use the current unit or the next smaller unit, we |
| // therefore nudge up the number with which the thresholding |
| // decision is made. However after the thresholding, we use the |
| // original values to ensure unbiased accuracy (to the extent of |
| // double's capabilities). |
| int64_t roundedQuantity = floor(quantity * (1 + DBL_EPSILON)); |
| intValues[i] = roundedQuantity; |
| |
| // Keep the residual of the quantity. |
| // For example: `3.6 feet`, keep only `0.6 feet` |
| // |
| // When the calculation is near enough +/- DBL_EPSILON, we round to |
| // zero. (We also ensure no negative values here.) |
| if ((quantity - roundedQuantity) / quantity < DBL_EPSILON) { |
| quantity = 0; |
| } else { |
| quantity -= roundedQuantity; |
| } |
| } else { // LAST ELEMENT |
| if (rounder == nullptr) { |
| // Nothing to do for the last element. |
| break; |
| } |
| |
| // Round the last value |
| // TODO(ICU-21288): get smarter about precision for mixed units. |
| number::impl::DecimalQuantity quant; |
| quant.setToDouble(quantity); |
| rounder->apply(quant, status); |
| if (U_FAILURE(status)) { |
| return result; |
| } |
| quantity = quant.toDouble(); |
| if (i == 0) { |
| // Last element is also the first element, so we're done |
| break; |
| } |
| |
| // Check if there's a carry, and bubble it back up the resulting intValues. |
| int64_t carry = floor(unitConverters_[i]->convertInverse(quantity) * (1 + DBL_EPSILON)); |
| if (carry <= 0) { |
| break; |
| } |
| quantity -= unitConverters_[i]->convert(carry); |
| intValues[i - 1] += carry; |
| |
| // We don't use the first converter: that one is for the input unit |
| for (int32_t j = i - 1; j > 0; j--) { |
| carry = floor(unitConverters_[j]->convertInverse(intValues[j]) * (1 + DBL_EPSILON)); |
| if (carry <= 0) { |
| break; |
| } |
| intValues[j] -= round(unitConverters_[j]->convert(carry)); |
| intValues[j - 1] += carry; |
| } |
| } |
| } |
| |
| // Package values into Measure instances in result: |
| for (int i = 0, n = unitConverters_.length(); i < n; ++i) { |
| if (i < n - 1) { |
| Formattable formattableQuantity(intValues[i] * sign); |
| // Measure takes ownership of the MeasureUnit* |
| MeasureUnit *type = new MeasureUnit(units_[i]->copy(status).build(status)); |
| if (result.emplaceBackAndCheckErrorCode(status, formattableQuantity, type, status) == |
| nullptr) { |
| // Ownership wasn't taken |
| U_ASSERT(U_FAILURE(status)); |
| delete type; |
| } |
| if (U_FAILURE(status)) { |
| return result; |
| } |
| } else { // LAST ELEMENT |
| // Add the last element, not an integer: |
| Formattable formattableQuantity(quantity * sign); |
| // Measure takes ownership of the MeasureUnit* |
| MeasureUnit *type = new MeasureUnit(units_[i]->copy(status).build(status)); |
| if (result.emplaceBackAndCheckErrorCode(status, formattableQuantity, type, status) == |
| nullptr) { |
| // Ownership wasn't taken |
| U_ASSERT(U_FAILURE(status)); |
| delete type; |
| } |
| if (U_FAILURE(status)) { |
| return result; |
| } |
| U_ASSERT(result.length() == i + 1); |
| U_ASSERT(result[i] != nullptr); |
| } |
| } |
| |
| MaybeStackVector<Measure> orderedResult; |
| int32_t unitsCount = outputUnits_.length(); |
| U_ASSERT(unitsCount == units_.length()); |
| Measure **arr = result.getAlias(); |
| // O(N^2) is fine: mixed units' unitsCount is usually 2 or 3. |
| for (int32_t i = 0; i < unitsCount; i++) { |
| for (int32_t j = i; j < unitsCount; j++) { |
| // Find the next expected unit, and swap it into place. |
| U_ASSERT(result[j] != nullptr); |
| if (result[j]->getUnit() == *outputUnits_[i]) { |
| if (j != i) { |
| Measure *tmp = arr[j]; |
| arr[j] = arr[i]; |
| arr[i] = tmp; |
| } |
| } |
| } |
| } |
| |
| return result; |
| } |
| |
| } // namespace units |
| U_NAMESPACE_END |
| |
| #endif /* #if !UCONFIG_NO_FORMATTING */ |
