| Table 1 How SA 2.0 rates, according to characteristics fundamental to all GIS products. | ||
| Criteria | Descriptions | Ratings |
| Blending Raster and Vector Data | Traditional raster GIS does little or no integration of vector data. However, the ability to directly integrate vector and raster data can have a dramatic impact on analysis. You can pose questions such as, “What is the fastest path(least-cost route) from the state capital to the southern edge of the county line?” | Strength: SA lets you integrate vector sources with cell-based raster data, including vector overlay on raster data, mask application, and grouping of raster areas inside vector polygons. |
| Neighborhood/Filtering Operations | This is a wide range of filtering operations that includes simple math (sum, max, min) as well as complex filters. Neighborhood functions let you define irregular areas, otherwise known asneighborhoods — donuts and wedges, for example. |
Strength: SA offers an extensive library of operations for dealing with irregular neighborhoods and filtering functions. |
| Hydrological and Surface Flow Operations | These operations let analysts identify stream networks, flow direction, flow length, sink locations, and watershed boundaries, among others. |
Strength: SA provides a robust library for analyzing surface and hydrological problems. |
| Buffering, Cost Surface, and Least Cost | These three functions are complementary and critical to most analysis. Buffering is a means of creating distance rings from starting points. Cost surfaces also radiate rings based on aggregated travel or cost. And least cost is the most efficient or optimum path from the starting point to a distant point of a cost surface. | Strength: SA provides a robust library for buffering and cost surface operations. |
| 3D Visualization and View Shed Operations | This is a requirement often demanded of raster analysis and encompasses features from the modest angle-of-view or digital-elevation model (DEM), to the ability to “fly through” your object. |
Basic: The default 3D capabilities in SA provide only basic viewing. Extension: However, with the purchase of 3D Analyst, the user acquires robust 3D capabilities. |
| Slope and Aspect Characterization | Slope and aspect computation is a traditional component of a raster GIS and includes convexity, concavity, length, and illumination. |
Basic: SA provides the standard functionality for slope. |
| Statistical and Geostatistical Operations | Raster GIS is replete with the need for statistical analysis. These operations range from traditional neighborhood statistics to advanced functions such as logistic regression, trend surface, and nonlinear regression, among others. |
Basic: SA provides only fundamental statistics. Extension: Users can purchase Splus for ArcView, which affords exhaustive statistical analysis. |
| Interpolation Operations | This function set lets you extrapolate a full raster data set from sample input data. As a result, analysts can define contours of the entire surface with sample data. |
Strength: SA provides an extensive array of interpolation operations, including kriging, splining, and weighted inverse distance. |