ClickHouse/src/Functions/geoToH3.cpp
2020-10-14 17:04:50 +03:00

97 lines
3.0 KiB
C++

#include <array>
#include <math.h>
#include <Columns/ColumnsNumber.h>
#include <DataTypes/DataTypesNumber.h>
#include <Functions/FunctionFactory.h>
#include <Functions/IFunctionImpl.h>
#include <Common/typeid_cast.h>
#include <ext/range.h>
#include <h3api.h>
namespace DB
{
namespace ErrorCodes
{
extern const int ILLEGAL_TYPE_OF_ARGUMENT;
}
namespace
{
/// Implements the function geoToH3 which takes 3 arguments (latitude, longitude and h3 resolution)
/// and returns h3 index of this point
class FunctionGeoToH3 : public IFunction
{
public:
static constexpr auto name = "geoToH3";
static FunctionPtr create(const Context &) { return std::make_shared<FunctionGeoToH3>(); }
std::string getName() const override { return name; }
size_t getNumberOfArguments() const override { return 3; }
bool useDefaultImplementationForConstants() const override { return true; }
DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
{
const auto * arg = arguments[0].get();
if (!WhichDataType(arg).isFloat64())
throw Exception(
"Illegal type " + arg->getName() + " of argument " + std::to_string(1) + " of function " + getName() + ". Must be Float64",
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
arg = arguments[1].get();
if (!WhichDataType(arg).isFloat64())
throw Exception(
"Illegal type " + arg->getName() + " of argument " + std::to_string(2) + " of function " + getName() + ". Must be Float64",
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
arg = arguments[2].get();
if (!WhichDataType(arg).isUInt8())
throw Exception(
"Illegal type " + arg->getName() + " of argument " + std::to_string(3) + " of function " + getName() + ". Must be UInt8",
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
return std::make_shared<DataTypeUInt64>();
}
void executeImpl(ColumnsWithTypeAndName & columns, const ColumnNumbers & arguments, size_t result, size_t input_rows_count) const override
{
const auto * col_lon = columns[arguments[0]].column.get();
const auto * col_lat = columns[arguments[1]].column.get();
const auto * col_res = columns[arguments[2]].column.get();
auto dst = ColumnVector<UInt64>::create();
auto & dst_data = dst->getData();
dst_data.resize(input_rows_count);
for (const auto row : ext::range(0, input_rows_count))
{
const double lon = col_lon->getFloat64(row);
const double lat = col_lat->getFloat64(row);
const UInt8 res = col_res->getUInt(row);
GeoCoord coord;
coord.lon = degsToRads(lon);
coord.lat = degsToRads(lat);
H3Index hindex = geoToH3(&coord, res);
dst_data[row] = hindex;
}
columns[result].column = std::move(dst);
}
};
}
void registerFunctionGeoToH3(FunctionFactory & factory)
{
factory.registerFunction<FunctionGeoToH3>();
}
}