| 摘要 |
To group items in an array, gap data are obtained indicating gaps between items. The gap data are used to obtain threshold data, which are then used to obtain grouping data. The gaps could, for example, be distances between items in a two-dimensional array or differences between values at which items occur in a one-dimensional array. The threshold data indicate a threshold. The threshold would produce a number of groups of the items that is stable across a range of thresholds, and the range of thresholds meets a criterion for largeness of a range. The criterion can require, for example, that the range be larger than the stable range of thresholds of any other number in a set of numbers of groups. The threshold can be obtained iteratively by applying a candidate threshold for each iteration. The candidate thresholds can be incremented, and the iterations can be counted to find a number of groups meeting the criterion. Or the candidate thresholds can be increased by differences between gaps, and a running sum of threshold ranges can be used to find a number of groups meeting the criterion. The threshold can also be obtained directly by finding the largest difference between gap extents and obtaining a threshold within the largest difference. Many types of grouping can be performed, including spatial clustering, segmentation of partially bounded regions, segmentation by local width, and global and local similarity grouping.
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