A New Point Access Method Based on Wavelet Trees
نویسندگان
چکیده
The development of index structures that allow e cient retrieval of spatial objects has been a topic of interest in the last decades. Most of these structures have been designed for secondary memory. However, in the last years the price of memory has decreased drastically. Nowadays it is feasible to place complete spatial indexes in main memory. In this paper we focus in a subcategory of spatial indexes named Point Access Methods. These indexes are designed to solve the problem of indexing points. We present a new index structure designed for two dimensions and main memory that keeps a good trade-o between the space needed to store the index and its search e ciency. Our structure is based on a wavelet tree, which was originally designed to represent sequences, but has been successfully used as an index in areas like information retrieval or image compression.
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