#include "config.h" #if USE_H3 #include #include #include #include #include #include #include #include #include namespace DB { namespace ErrorCodes { extern const int ILLEGAL_TYPE_OF_ARGUMENT; extern const int ARGUMENT_OUT_OF_BOUND; extern const int ILLEGAL_COLUMN; } namespace { // Average metric edge length of H3 hexagon. The edge length `e` for given resolution `res` can // be used for converting metric search radius `radius` to hexagon search ring size `k` that is // used by `H3kRing` function. For small enough search area simple flat approximation can be used, // i.e. the smallest `k` that satisfies relation `3 k^2 - 3 k + 1 >= (radius / e)^2` should be // chosen class FunctionH3EdgeLengthM : public IFunction { public: static constexpr auto name = "h3EdgeLengthM"; static FunctionPtr create(ContextPtr) { return std::make_shared(); } std::string getName() const override { return name; } size_t getNumberOfArguments() const override { return 1; } bool useDefaultImplementationForConstants() const override { return true; } bool isSuitableForShortCircuitArgumentsExecution(const DataTypesWithConstInfo & /*arguments*/) const override { return false; } DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override { const auto * arg = arguments[0].get(); if (!WhichDataType(arg).isUInt8()) throw Exception( ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT, "Illegal type {} of argument {} of function {}. Must be UInt8", arg->getName(), 1, getName()); return std::make_shared(); } ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t input_rows_count) const override { auto non_const_arguments = arguments; for (auto & argument : non_const_arguments) argument.column = argument.column->convertToFullColumnIfConst(); const auto * column = checkAndGetColumn(non_const_arguments[0].column.get()); if (!column) throw Exception( ErrorCodes::ILLEGAL_COLUMN, "Illegal type {} of argument {} of function {}. Must be UInt8", arguments[0].column->getName(), 1, getName()); const auto & data = column->getData(); auto dst = ColumnVector::create(); auto & dst_data = dst->getData(); dst_data.resize(input_rows_count); for (size_t row = 0; row < input_rows_count; ++row) { const UInt8 resolution = data[row]; if (resolution > MAX_H3_RES) throw Exception( ErrorCodes::ARGUMENT_OUT_OF_BOUND, "The argument 'resolution' ({}) of function {} is out of bounds because the maximum resolution in H3 library is {}", toString(resolution), getName(), MAX_H3_RES); Float64 res = getHexagonEdgeLengthAvgM(resolution); dst_data[row] = res; } return dst; } }; } REGISTER_FUNCTION(H3EdgeLengthM) { factory.registerFunction(); } } #endif