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极限在一个空间的代码的平均长度上
1Department of Computer Science, University of Salerno, 84084 Fisciano, Italy.
Entropy (Basel, Switzerland)
|April 26, 2024
概括
本研究介绍了一种快速的算法,用于创建没有前的代码,其中一个特殊的"空间"符号只出现在最后. 这些代码几乎是最佳的,平均长度接近理论最小值.
科学领域:
- 信息理论 信息理论
- 计算机科学 计算机科学
- 编码理论编码理论
背景情况:
- 没有前的代码是数据压缩和通信的基础.
- 限制符号的放置,就像一个"空间"符号一样,在代码构建中引入了独特的挑战.
- 现有的方法可能无法有效处理特定的符号约束.
研究的目的:
- 开发一种高效的算法,用于构建带有限制的"空间"符号的无前代码.
- 在这种约束下实现接近最佳的代码长度.
- 分析这些代码的理论界限.
主要方法:
- 开发用于代码构建的线性时间算法.
- 在受约束代码和一对一代码之间建立连接.
- 平均代码长度上下限的推导.
主要成果:
- 介绍了一种线性时间算法,用于构建没有前的代码,末尾是"空间"符号.
- 构建的代码被证明是几乎最佳的,平均长度与最小可能的最多不同.
- 对这些特定代码的平均代码长度与源产生了新的边界.
结论:
- 拟议的算法提供了一种有效的方法,用于生成具有特定符号约束的高质量前免费代码.
- 这些发现加深了对不同类代码之间的关系的理解.
- 这项工作为编码理论的理论基础做出了贡献,对数据压缩有实际意义.
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