LazySorted: A Lazily, Partially Sorted Python List

• Main Author: Naftali Harris
• Format: Article
• Language: English
• Published: Foundation for Open Access Statistics 2015-06-01
• Series: Journal of Statistical Software
• Online Access: http://www.jstatsoft.org/index.php/jss/article/view/2265

LazySorted is a Python C extension implementing a partially and lazily sorted list data structure. It solves a common problem faced by programmers, in which they need just part of a sorted list, like its middle element (the median), but sort the entire list to get it. LazySorted presents them with the abstraction that they are working with a fully sorted list, while actually only sorting the list partially with quicksort partitions to return the requested sub-elements. This enables programmers to use naive "sort first" algorithms but nonetheless attain linear run-times when possible. LazySorted may serve as a drop-in replacement for the built-in sorted function in most cases, and can sometimes achieve run-times more than 7 times faster.