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Jaguc - a Software package for Environmental Diversity Analyses
The new program package JAGUC is a tool that bridges the gap between computational and biological sciences that enables biologists to process large sequence data sets in order to infer biological meaning from hundreds of thousands of raw sequence data. Expand
Analysis of Pivot Sampling in Dual-Pivot Quicksort: A Holistic Analysis of Yaroslavskiy’s Partitioning Scheme
It turns out that the asymmetries in Yaroslavskiy’s algorithm render pivots with a systematic skew more efficient than the symmetric choice, which means dual-pivot Quicksort needs significantly less I/Os, both with and without pivot sampling. Expand
Average Case Analysis of Java 7's Dual Pivot Quicksort
Recently, a new Quicksort variant due to Yaroslavskiy was chosen as standard sorting method for Oracle's Java 7 runtime library. The decision for the change was based on empirical studies showingExpand
Building Fences Straight and High: An Optimal Algorithm for Finding the Maximum Length You Can Cut k Times from Given Sticks
This work analyzes the structure of the envy-free stick-division problem and shows that it essentially reduces to a single call of a selection algorithm; it is shown that this algorithm is an optimal linear-time algorithm. Expand
Average Case and Distributional Analysis of Dual-Pivot Quicksort
Surprisingly, Yaroslavskiy's algorithm needs sightly more Bytecode instructions than a simple implementation of classic Quicksort—contradicting observed running times; and it is shown that the (suitably normalized) costs of YaroslavSKY's algorithm converge to a random variable whose distribution is characterized by a fixed-point equation. Expand
Dual-Pivot Quicksort and Beyond: Analysis of Multiway Partitioning and Its Practical Potential
This dissertation conducts a mathematical average-case analysis of multiway Quicksort including the important optimization to choose pivots from a sample of the input and proposes a parametric template algorithm that covers all practically relevant partitioning methods as special cases, and analytically investigates in depth what effect the parameters of the generic quicksort have on its performance. Expand
Java 7's Dual-Pivot Quicksort
This thesis focuses on the precise and detailed average case analysis of Quicksort, aiming at the flavor of Knuth's series “The Art of Computer Programming”, and tries to understand the efficiency of the algorithms at different levels of abstraction. Expand
Engineering Java 7's Dual Pivot Quicksort Using MaLiJan
This paper uses the new tool MaLiJAn to confirm that asymmetric pivot choices are preferable to symmetric ones for this Quicksort variant asymptotically for combinatorial cost measures such as the total number of executed instructions. Expand
Dual-pivot and beyond: The potential of multiway partitioning in quicksort
This dissertation proved by a comprehensive mathematical analysis of all sensible Quicksort partitioning variants that (a) indeed there is hardly any advantage to be gained from multiway partitioning in terms of the number of comparisons, but (b) multi way partitioning does significantly reduce the amount of data to be moved between CPU and main memory. Expand
QuickXsort: A Fast Sorting Scheme in Theory and Practice
If pivots are chosen as medians of (not too fast) growing size samples, the average number of comparisons of QuickXsort and X differ only by o ( n )-terms, and the average-case number of compared can be reduced down to 1.4112n + o(n). Expand