栅格数据表示空间信息的不确定性初探

首先阐述了栅格结构在地形表达方面所表现出来的两大优势,正因为这些优势使得栅格结构能在GIS中得到广泛应用。其次,分析了由于栅格结构自身的特点,导致了在处理地形表面数据时,会有基于点和基于面两种不同的处理方式,并由此会产生解释格网属性值和确定属性值定位这两方面的不确定性。然后,提出了解决该问题的方法,即将栅格数据结构分为像素模型和格网模型两种形式。最后给出了两个典型例子,来说明若将不同的栅格数据图层等同对待会产生的结果误差情况,提醒用户使用栅格数据时注意的事项。

A Preliminary Discussion on Uncertainty of the Spatial Information Presentation by using Raster Data

Two major advantages in terrain expression by using raster data structure were expounded at the beginning of this paper. Because of these, the application of raster data structure in GIS is very wide. Secondly, the paper analyzed that, for the characteristic of raster data structure itself, terrain surfaces were handled in two different kinds of ways: point-based and area-based representations. And the results would have ambiguities with the interpretation of the values in lattices and uncertainty in identifying the location of those values. Then the paper proposed the solving method that was distinguishing the raster data structure into lattice models and pixel models. Finally, the paper gave two typical examples to illuminate that the result would have errors when treating different raster maps as if they were same, and reminded all users in GIS need to take care.