ClickHouse/src/Functions/h3toGeo.cpp
2022-01-22 23:02:14 -08:00

107 lines
3.1 KiB
C++

#include "config_functions.h"
#if USE_H3
#include <array>
#include <math.h>
#include <Columns/ColumnArray.h>
#include <Columns/ColumnTuple.h>
#include <Columns/ColumnsNumber.h>
#include <DataTypes/DataTypeTuple.h>
#include <DataTypes/DataTypesNumber.h>
#include <Functions/FunctionFactory.h>
#include <Functions/IFunction.h>
#include <Common/typeid_cast.h>
#include <h3api.h>
namespace DB
{
namespace ErrorCodes
{
extern const int ILLEGAL_TYPE_OF_ARGUMENT;
extern const int ILLEGAL_COLUMN;
}
namespace
{
/// Implements the function h3ToGeo which takes a single argument (h3Index)
/// and returns the longitude and latitude that correspond to the provided h3 index
class FunctionH3ToGeo : public IFunction
{
public:
static constexpr auto name = "h3ToGeo";
static FunctionPtr create(ContextPtr) { return std::make_shared<FunctionH3ToGeo>(); }
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).isUInt64())
throw Exception(
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT,
"Illegal type {} of argument {} of function {}. Must be UInt64",
arg->getName(), 1, getName());
return std::make_shared<DataTypeTuple>(
DataTypes{std::make_shared<DataTypeFloat64>(), std::make_shared<DataTypeFloat64>()},
Strings{"longitude", "latitude"});
}
ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t input_rows_count) const override
{
const auto * column = checkAndGetColumn<ColumnUInt64>(arguments[0].column.get());
if (!column)
throw Exception(
ErrorCodes::ILLEGAL_COLUMN,
"Illegal type {} of argument {} of function {}. Must be UInt64.",
arguments[0].type->getName(),
1,
getName());
const auto & data = column->getData();
auto latitude = ColumnFloat64::create(input_rows_count);
auto longitude = ColumnFloat64::create(input_rows_count);
ColumnFloat64::Container & lon_data = longitude->getData();
ColumnFloat64::Container & lat_data = latitude->getData();
for (size_t row = 0; row < input_rows_count; ++row)
{
H3Index h3index = data[row];
LatLng coord{};
cellToLatLng(h3index,&coord);
lon_data[row] = radsToDegs(coord.lng);
lat_data[row] = radsToDegs(coord.lat);
}
MutableColumns columns;
columns.emplace_back(std::move(longitude));
columns.emplace_back(std::move(latitude));
return ColumnTuple::create(std::move(columns));
}
};
}
void registerFunctionH3ToGeo(FunctionFactory & factory)
{
factory.registerFunction<FunctionH3ToGeo>();
}
}
#endif