User avatar admin

Translation uploaded
If we globally define the macro `BOOST_UNORDERED_ENABLE_STATS`, open-addressing and concurrent containers will calculate some internal statistics directly correlated to the quality of the hash function:
If we globally define the macro若在全局定义宏 `BOOST_++_++UNORDERED_++_++ENABLE_++_++STATS`, open-addressing and concurrent containers will calculate some internal statistics directly correlated to the quality of the hash function: ，开放寻址容器与并发容器将计算与哈希函数质量直接相关的内部统计信息：
06/05/2026
User avatar admin

Translation uploaded
Container Statistics
Container Statistics容器统计信息
06/05/2026
User avatar admin

Translation uploaded
By setting the `link:../../../../container_hash/doc/html/hash.html#ref_hash_is_avalanchinghash[hash_is_avalanching]` trait, we inform Boost.Unordered that `my_string_hash_function` is of sufficient quality to be used directly without any post-mixing safety net. This comes at the risk of degraded performance in the cases where the hash function is not as well-behaved as we've declared.
By setting the `通过设置 link:../../../../container_hash/doc/html/hash.html#ref_hash_is_avalanchinghash[`hash_is_avalanching]` trait, we inform Boost.Unordered that `my_string_hash_function` is of sufficient quality to be used directly without any post-mixing safety net. This comes at the risk of degraded performance in the cases where the hash function is not as well-behaved as we've declared.++_++is++_++avalanching`] 特征，我们告知Boost.Unordered： `my++_++string++_++hash++_++function` 具有足够高的质量，无需任何后混合处理安全网即可直接使用。但这样做的风险在于，如果哈希函数的表现未达到我们声明的理想状态，则可能导致性能下降。
06/05/2026
User avatar admin

Translation uploaded
Even if your supplied hash function does not conform to the uniform behavior required by open addressing, chances are that the performance of Boost.Unordered containers will be acceptable, because the library executes an internal __post-mixing__ step that improves the statistical properties of the calculated hash values. This comes with an extra computational cost; if you'd like to opt out of post-mixing, annotate your hash function as follows:
Even if your supplied hash function does not conform to the uniform behavior required by open addressing, chances are that the performance of Boost.Unordered containers will be acceptable, because the library executes an internal __post-mixing__ step that improves the statistical properties of the calculated hash values. This comes with an extra computational cost; if you'd like to opt out of post-mixing, annotate your hash function as follows:即使提供的哈希函数不符合开放寻址所需的均匀分布特性，Boost.Unordered容器的性能通常仍可接受，这是因为库会执行内部__后混合处理__步骤来改善计算哈希值的统计特性。当然这会带来额外的计算开销；若希望禁用后混合处理功能，请按以下方式对哈希函数进行注解：
06/05/2026
User avatar admin

Translation uploaded
Hash Post-mixing and the Avalanching Property
Hash Post-mixing and the Avalanching Property哈希后混合处理与雪崩效应属性
06/05/2026
User avatar admin

Translation uploaded
The rest of this section applies only to open-addressing and concurrent containers.
The rest of this section applies only to open-addressing and concurrent containers.本节剩余的内容仅适用于开放寻址容器与并发容器。
06/05/2026
User avatar admin

Translation uploaded
Closed-addressing containers in Boost.Unordered are fairly robust against hash functions with less-than-ideal quality, but open-addressing and concurrent containers are much more sensitive to this factor, and their performance can degrade dramatically if the hash function is not appropriate. In general, if you're using functions provided by or generated with link:../../../../container_hash/index.html[Boost.Hash^], the quality will be adequate, but you have to be careful when using alternative hash algorithms.
Closed-addressing containers in Boost.Unordered are fairly robust against hash functions with less-than-ideal quality, but open-addressing and concurrent containers are much more sensitive to this factor, and their performance can degrade dramatically if the hash function is not appropriate. In general, if you're using functions provided by or generated with link:../../../../container_hash/index.html[Boost.Hash^], the quality will be adequate, but you have to be careful when using alternative hash algorithms.Boost.Unordered 中的闭寻址容器对质量不理想的哈希函数具有较好的鲁棒性，但开放寻址和并发容器对此因素更为敏感。如果哈希函数选择不当，其性能会出现显著下降。通常，使用由 link:../../../../container_hash/index.html[Boost.Hash] 提供或生成的函数可确保质量达标，但在使用其他哈希算法时则需要特别谨慎。
06/05/2026
User avatar admin

Translation uploaded
In order to work properly, hash tables require that the supplied hash function be of __good quality__, roughly meaning that it uses its `std::size_t` output space as uniformly as possible, much like a random number generator would do —except, of course, that the value of a hash function is not random but strictly determined by its input argument.
In order to work properly, hash tables require that the supplied hash function be of __good quality__, roughly meaning that it uses its `std::size_t` output space as uniformly as possible, much like a random number generator would do —except, of course, that the value of a hash function is not random but strictly determined by its input argument.为了正常工作，哈希表要求提供的哈希函数具有__高质量__，这大致意味着它应尽可能均匀地使用其 `std::size++_++t` 输出空间，就像随机数生成器那样——当然，不同之处在于哈希函数的值并非随机，而是由其输入参数严格决定。
06/05/2026
User avatar admin

Translation uploaded
:idprefix: hash_quality_
:idprefix: hash_quality_
06/05/2026
User avatar admin

Translation uploaded
[#hash_quality] = Hash Quality
[#hash_quality] = Hash Quality哈希质量
06/05/2026
User avatar admin

File uploaded
Processed 34 strings from the uploaded files (skipped: 0, not found: 0, updated: 34).
File upload mode: Add as translation 06/05/2026
User avatar admin

Translation uploaded
Returns the container's key equality function..
Returns the container's key equality function..返回容器的键相等性函数。
06/05/2026
User avatar admin

Translation uploaded
`key_equal key_eq() const`
`key_equal key_eq() const`
06/05/2026
User avatar admin

Translation uploaded
Returns the container's hash function.
Returns the container's hash function.返回容器的哈希函数。
06/05/2026
User avatar admin

Translation uploaded
`hasher hash_function() const`
`hasher hash_function() const`
06/05/2026
User avatar admin

Translation uploaded
Description
Description描述
06/05/2026
User avatar admin

Translation uploaded
Method
Method方法
06/05/2026
User avatar admin

Translation uploaded
See the link:../../../../container_hash/index.html[Boost.Hash documentation^] for more detail on how to do this. Remember that it relies on extensions to the standard - so it won't work for other implementations of the unordered associative containers, you'll need to explicitly use Boost.Hash.
See the有关如何执行此操作的更多详细信息，请参阅 link:../../../../container_hash/index.html[Boost.Hash documentation^] for more detail on how to do this. Remember that it relies on extensions to the standard - so it won't work for other implementations of the unordered associative containers, you'll need to explicitly use文档^]。请记住，它依赖于标准扩展—因此它不适用于无序关联容器的其他实现，你需要显式使用 Boost.Hash.。
06/05/2026
User avatar admin

Translation uploaded
boost::unordered_multiset<point> points; ```
boost::unordered_multiset<point> points; ```</point>
06/05/2026
User avatar admin

Translation uploaded
std::size_t hash_value(point const& p) { std::size_t seed = 0; boost::hash_combine(seed, p.x); boost::hash_combine(seed, p.y); return seed; }
std::size_t hash_value(point const&amp; p) { std::size_t seed = 0; boost::hash_combine(seed, p.x); boost::hash_combine(seed, p.y); return seed; }
06/05/2026

Search