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add C++14 constexpr version: random generator

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bolero-MURAKAMI 2013-11-05 17:39:11 +09:00
parent 2c9f0647f4
commit 230630b45b
6 changed files with 44 additions and 2 deletions
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17
sprout/random/shuffle_order.hpp
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@ -124,7 +124,7 @@ namespace sprout {
: sprout::math::less(brange, sprout::numeric_limits<BaseUnsigned>::max() / k) ? BaseUnsigned(k * off / (brange + 1))
: sprout::math::less(brange, sprout::numeric_limits<std::uintmax_t>::max() / k)
? static_cast<BaseUnsigned>(static_cast<std::uintmax_t>(off) * k / (static_cast<std::uintmax_t>(brange) + 1))
//: static_cast<BaseUnsigned>(sprout::random::detail::muldiv(off, k, static_cast<std::uintmax_t>(brange) + 1)) // ???
// : static_cast<BaseUnsigned>(sprout::random::detail::muldiv(off, k, static_cast<std::uintmax_t>(brange) + 1)) // ???
: (SPROUT_ASSERT_MSG(0, "Sorry, not implemented."), sprout::random::random_result<shuffle_order_engine>())
);
}
@ -144,6 +144,21 @@ namespace sprout {
SPROUT_CONSTEXPR result_type max() const SPROUT_NOEXCEPT {
return rng_.max();
}
SPROUT_CXX14_CONSTEXPR result_type operator()() {
typedef typename std::make_unsigned<result_type>::type base_unsigned;
base_unsigned const brange = sprout::random::detail::subtract<result_type>()(max(), min());
base_unsigned const off = sprout::random::detail::subtract<result_type>()(y_, min());
base_unsigned j = k == 1 ? base_unsigned(0)
: sprout::math::less(brange, sprout::numeric_limits<base_unsigned>::max() / k) ? base_unsigned(k * off / (brange + 1))
: sprout::math::less(brange, sprout::numeric_limits<std::uintmax_t>::max() / k)
? static_cast<base_unsigned>(static_cast<std::uintmax_t>(off) * k / (static_cast<std::uintmax_t>(brange) + 1))
// : static_cast<base_unsigned>(sprout::random::detail::muldiv(off, k, static_cast<std::uintmax_t>(brange) + 1)) // ???
: (SPROUT_ASSERT_MSG(0, "Sorry, not implemented."), base_unsigned(0))
;
y_ = v_[j];
v_[j] = static_cast<result_type>(rng_());
return y_;
}
SPROUT_CONSTEXPR sprout::random::random_result<shuffle_order_engine> const operator()() const {
typedef typename std::make_unsigned<result_type>::type base_unsigned;
return generate(