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authorAnton Samokhvalov <pg83@yandex.ru>2022-02-10 16:45:15 +0300
committerDaniil Cherednik <dcherednik@yandex-team.ru>2022-02-10 16:45:15 +0300
commit72cb13b4aff9bc9cf22e49251bc8fd143f82538f (patch)
treeda2c34829458c7d4e74bdfbdf85dff449e9e7fb8 /util/random/common_ops.h
parent778e51ba091dc39e7b7fcab2b9cf4dbedfb6f2b5 (diff)
downloadydb-72cb13b4aff9bc9cf22e49251bc8fd143f82538f.tar.gz
Restoring authorship annotation for Anton Samokhvalov <pg83@yandex.ru>. Commit 1 of 2.
Diffstat (limited to 'util/random/common_ops.h')
-rw-r--r--util/random/common_ops.h198
1 files changed, 99 insertions, 99 deletions
diff --git a/util/random/common_ops.h b/util/random/common_ops.h
index 602eede351..f9c50f12ac 100644
--- a/util/random/common_ops.h
+++ b/util/random/common_ops.h
@@ -1,130 +1,130 @@
-#pragma once
-
-#include <util/system/defaults.h>
-#include <util/system/yassert.h>
-
-namespace NPrivate {
+#pragma once
+
+#include <util/system/defaults.h>
+#include <util/system/yassert.h>
+
+namespace NPrivate {
constexpr double ToRandReal1(const ui32 x) noexcept {
return x * (double)(1.0 / 4294967295.0);
- }
-
+ }
+
constexpr double ToRandReal2(const ui32 x) noexcept {
return x * (double)(1.0 / 4294967296.0);
- }
-
+ }
+
constexpr double ToRandReal3(const ui32 x) noexcept {
return ((double)x + 0.5) * (double)(1.0 / 4294967296.0);
- }
-
+ }
+
constexpr double ToRandReal1(const ui64 x) noexcept {
return (x >> 11) * (double)(1.0 / 9007199254740991.0);
- }
-
+ }
+
constexpr double ToRandReal2(const ui64 x) noexcept {
return (x >> 11) * (double)(1.0 / 9007199254740992.0);
- }
-
+ }
+
constexpr double ToRandReal3(const ui64 x) noexcept {
return ((x >> 12) + 0.5) * (double)(1.0 / 4503599627370496.0);
- }
-
+ }
+
constexpr double ToRandReal4(const ui64 x) noexcept {
return double(x * (double)(1.0 / 18446744073709551616.0L));
- }
-
- template <class T>
+ }
+
+ template <class T>
static inline ui64 ToRand64(T&& rng, ui32 x) noexcept {
- return ((ui64)x) | (((ui64)rng.GenRand()) << 32);
- }
-
- template <class T>
+ return ((ui64)x) | (((ui64)rng.GenRand()) << 32);
+ }
+
+ template <class T>
static constexpr ui64 ToRand64(T&&, ui64 x) noexcept {
- return x;
- }
-
- /*
- * return value in range [0, max) from any generator
- */
- template <class T, class TRandGen>
- static T GenUniform(T max, TRandGen&& gen) {
+ return x;
+ }
+
+ /*
+ * return value in range [0, max) from any generator
+ */
+ template <class T, class TRandGen>
+ static T GenUniform(T max, TRandGen&& gen) {
Y_VERIFY(max > 0, "Invalid random number range [0, 0)");
-
- const T randmax = gen.RandMax() - gen.RandMax() % max;
- T rand;
-
- while ((rand = gen.GenRand()) >= randmax) {
- /* no-op */
- }
-
- return rand % max;
- }
-}
-
-template <class TRandType, class T>
-struct TCommonRNG {
- using TResult = TRandType;
+
+ const T randmax = gen.RandMax() - gen.RandMax() % max;
+ T rand;
+
+ while ((rand = gen.GenRand()) >= randmax) {
+ /* no-op */
+ }
+
+ return rand % max;
+ }
+}
+
+template <class TRandType, class T>
+struct TCommonRNG {
+ using TResult = TRandType;
using result_type = TRandType;
-
+
inline T& Engine() noexcept {
- return static_cast<T&>(*this);
- }
-
- static constexpr TResult _Min = TResult(0);
- static constexpr TResult _Max = TResult(-1);
-
+ return static_cast<T&>(*this);
+ }
+
+ static constexpr TResult _Min = TResult(0);
+ static constexpr TResult _Max = TResult(-1);
+
static constexpr TResult RandMax() noexcept {
- return _Max;
- }
-
+ return _Max;
+ }
+
static constexpr TResult RandMin() noexcept {
- return _Min;
- }
-
- /* generates uniformly distributed random number on [0, t) interval */
+ return _Min;
+ }
+
+ /* generates uniformly distributed random number on [0, t) interval */
inline TResult Uniform(TResult t) noexcept {
- return ::NPrivate::GenUniform(t, Engine());
- }
-
- /* generates uniformly distributed random number on [f, t) interval */
+ return ::NPrivate::GenUniform(t, Engine());
+ }
+
+ /* generates uniformly distributed random number on [f, t) interval */
inline TResult Uniform(TResult f, TResult t) noexcept {
- return f + Uniform(t - f);
- }
-
- /* generates 64-bit random number for current(may be 32 bit) rng */
+ return f + Uniform(t - f);
+ }
+
+ /* generates 64-bit random number for current(may be 32 bit) rng */
inline ui64 GenRand64() noexcept {
- return ::NPrivate::ToRand64(Engine(), Engine().GenRand());
- }
-
- /* generates a random number on [0, 1]-real-interval */
+ return ::NPrivate::ToRand64(Engine(), Engine().GenRand());
+ }
+
+ /* generates a random number on [0, 1]-real-interval */
inline double GenRandReal1() noexcept {
- return ::NPrivate::ToRandReal1(Engine().GenRand());
- }
-
- /* generates a random number on [0, 1)-real-interval */
+ return ::NPrivate::ToRandReal1(Engine().GenRand());
+ }
+
+ /* generates a random number on [0, 1)-real-interval */
inline double GenRandReal2() noexcept {
- return ::NPrivate::ToRandReal2(Engine().GenRand());
- }
-
- /* generates a random number on (0, 1)-real-interval */
+ return ::NPrivate::ToRandReal2(Engine().GenRand());
+ }
+
+ /* generates a random number on (0, 1)-real-interval */
inline double GenRandReal3() noexcept {
- return ::NPrivate::ToRandReal3(Engine().GenRand());
- }
-
- /* generates a random number on [0, 1) with 53-bit resolution */
+ return ::NPrivate::ToRandReal3(Engine().GenRand());
+ }
+
+ /* generates a random number on [0, 1) with 53-bit resolution */
inline double GenRandReal4() noexcept {
- return ::NPrivate::ToRandReal4(Engine().GenRand64());
- }
-
- //compatibility stuff
+ return ::NPrivate::ToRandReal4(Engine().GenRand64());
+ }
+
+ //compatibility stuff
inline TResult operator()() noexcept {
- return Engine().GenRand();
- }
-
+ return Engine().GenRand();
+ }
+
static constexpr TResult max() noexcept {
- return T::RandMax();
- }
-
+ return T::RandMax();
+ }
+
static constexpr TResult min() noexcept {
- return T::RandMin();
- }
-};
+ return T::RandMin();
+ }
+};