Vector Geoprocessing Tools

A geoprocessing tool is one that systematically manipulates either the geometry or the attribute information or both of a vector GIS data file. It is used to perform various spatial operations and analyses on vector data.
These tools allow for tasks such as buffering, clipping, merging, intersecting, dissolving, and more. They provide the means to extract, transform, and analyze data within a geographic context, facilitating effective spatial analysis and decision-making processes.

 The photo above clearly shows the function of the 6 basic toolkits.


Basic six toolkits

  • Buffer
- creates a geometric area around vector features by using points, lines or polygons (input) at a specified distance of a feature or features (buffer width)

- can create variable distance buffers based on attribute value 

- use equidistant projection to center the point from that point, know the scale well and can draw buffer


  • Clip 
- subset tool

- large dataset to clip down into smaller subset/dataset

- clip operation takes 2 datasets: the dataset to be clipped and the datafile to clip it to

- efficient to isolate and store 1 dataset with a large geographic extent 

- not accepts more than 2 inputs at a time (only clip input dataset, another dataset can be clipped by)


  • Union

- logical OR / inclusive or (inclusive of both conditions)

- merge overlapping or adjacent features into a single representation

- maintains all input feature boundaries and attributes in the output feature class

- it preserves features from both layers to the same extent

- 2 total input features and produce 5 output features


  • Merge

- combines multiple input datasets of the same geometry type (points, lines, or polygons) into a (unified representation) single output dataset

- datasets have to be the same type

- number of features in the output is always the sum of all features in the input files


  • Intersect

- logical AND

- operates on multiple vector datasets, determining and retaining the common features that intersect or overlap in all the datasets 

- it is valid to intersect datasets with different geometry type

- it preserves attributes from all the data sets that overlap each other in the output

- accepts more than 2 inputs at a time, has 1 output feature


  • Dissolve

- combines adjacent or overlapping vector features with the same attribute value into a single feature

- can be used to simplify and aggregate vector data by removing boundaries between adjacent features with identical attribute values

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