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clickhouse: added missing file [#CONV-6318].

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Michael Kolupaev 2012-12-24 08:16:25 +00:00
parent 1b82540fa3
commit ea874ad1c5
1 changed files with 99 additions and 0 deletions
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99
dbms/include/DB/Functions/FunctionsRound.h Normal file
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#pragma once
#include <DB/Functions/FunctionsArithmetic.h>
#include <cmath> // log2()
namespace DB
{
/** Функции округления:
* roundToExp2 - вниз до ближайшей степени двойки;
* roundDuration - вниз до ближайшего из: 0, 1, 10, 30, 60, 120, 180, 240, 300, 600, 1200, 1800, 3600, 7200, 18000, 36000;
* roundAge - вниз до ближайшего из: 0, 18, 25, 35, 45.
*/
template<typename A>
struct RoundToExp2Impl
{
typedef A ResultType;
static inline A apply(A x)
{
return x <= 0 ? static_cast<A>(0) : (static_cast<A>(1) << static_cast<UInt64>(log2(static_cast<double>(x))));
}
};
template<>
struct RoundToExp2Impl<Float32>
{
typedef Float32 ResultType;
static inline Float32 apply(Float32 x)
{
return static_cast<Float32>(x < 1 ? 0. : pow(2., floor(log2(x))));
}
};
template<>
struct RoundToExp2Impl<Float64>
{
typedef Float64 ResultType;
static inline Float64 apply(Float64 x)
{
return x < 1 ? 0. : pow(2., floor(log2(x)));
}
};
template<typename A>
struct RoundDurationImpl
{
typedef UInt16 ResultType;
static inline ResultType apply(A x)
{
return x < 1 ? 0
: (x < 10 ? 1
: (x < 30 ? 10
: (x < 60 ? 30
: (x < 120 ? 60
: (x < 180 ? 120
: (x < 240 ? 180
: (x < 300 ? 240
: (x < 600 ? 300
: (x < 1200 ? 600
: (x < 1800 ? 1200
: (x < 3600 ? 1800
: (x < 7200 ? 3600
: (x < 18000 ? 7200
: (x < 36000 ? 18000
: 36000))))))))))))));
}
};
template<typename A>
struct RoundAgeImpl
{
typedef UInt8 ResultType;
static inline ResultType apply(A x)
{
return x < 18 ? 0
: (x < 25 ? 18
: (x < 35 ? 25
: (x < 45 ? 35
: 45)));
}
};
struct NameRoundToExp2 { static const char * get() { return "roundToExp"; } };
struct NameRoundDuration { static const char * get() { return "roundDuration"; } };
struct NameRoundAge { static const char * get() { return "roundAge"; } };
typedef FunctionUnaryArithmetic<RoundToExp2Impl, NameRoundToExp2> FunctionRoundToExp2;
typedef FunctionUnaryArithmetic<RoundDurationImpl, NameRoundDuration> FunctionRoundDuration;
typedef FunctionUnaryArithmetic<RoundAgeImpl, NameRoundAge> FunctionRoundAge;
}