1. boolean operations
operators: true or false(0 or 1)
resulting from: union(logical or ) ∨
intersection(logical and)
negation(logical not)
elclusion(XOR) of 2 or more sets a、b两个值不相同，则异或结果为1。如果a、b两个值相同，异或结果为0
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2. buffering
buffering is a process that creates an area (polygon) around a feature, the result is a new polygon layer
3. erasing
or deleting data from a layer to create a new layer can be implemented in one of two main ways
4. extracting
reverse with erasing, maintaing only specidied areas
5. merging
removing unnecessary or superfluous polygon boundaries
6. updating
creates a new layer based on data in an existing layer by updating, or altering, a portion of the data(spatial or attribute) based on another, independent layer
7. vector overlay
combining two paper maps into one new paper map