Difference
What is Difference analysis?
Difference analysis in GIS refers to the process of identifying the spatial features that are unique to one dataset and do not overlap with features from another dataset. This analysis removes any overlapping areas and highlights only the non-overlapping regions in the first dataset relative to the second dataset. Essentially, it compares two spatial layers and extracts portions of geometries that exist solely in the source layer but not in the target layer.
When would you use Difference analysis?
Difference analysis is especially useful in scenarios where it is essential to identify and manage distinct regions that are exclusively part of one dataset but not another. Common use cases include environmental studies, where you may need to determine areas of land that remain unaffected by certain events such as development projects or natural disasters, and urban planning, where it is crucial to delineate land that remains available for potential zoning applications after accounting for existing infrastructure.
FAQs
How do you perform a Difference analysis in Atlas?
In Atlas, the Difference analysis can be executed by selecting the 'Difference' option under data actions in the right panel. You need to input the two datasets you wish to compare: the source dataset and the target dataset from which you want to differentiate. After setting your parameters, click 'run' to generate the non-overlapping regions.
What are the data input requirements for a Difference analysis?
Both input datasets should be spatial layers that are compatible for comparison. Generally, these need to be vector data layers, such as polygons, which can be spatially compared for overlaps and unique areas.
Can the Difference analysis be performed on multiple datasets simultaneously?
The analysis is typically conducted between two datasets at a time in Atlas. If multiple datasets are involved, you can iteratively run the Difference analysis by comparing each dataset pairwise as required.
What is the output of a Difference analysis?
The output of a Difference analysis is a new spatial layer or dataset that includes only the regions of the source dataset that do not overlap with the target dataset. These non-overlapping areas are extracted as new geometries.