Unit AM4 Basic analytical operations

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Exercise Data

Type of Data Four simple datasets are used for these examples including 3 vector and at least one raster data file. Each file should generally overlap the region of the other files so that comparison operations can be done in the exercises:

  1. points - several dozen points roughly grouped together
  2. lines - a simple network of lines would be ideal
  3. areas - one or more polygons
  4. raster - with some simple grouped classes, not too noisy and similar in appearance to points, lines or areas.


Specific Examples All examples in this instance of the training are from the North Carolina demonstration dataset shapefiles and grids.

  1. points - bus stop locations - busstopsall.shp
  2. lines - stream network - streams.shp
  3. areas - lakes - lakes.shp
  4. raster:
    1. a single point-like feature class - facility.grd
    2. road linework - roadsmajor.grd

Buffering a Multiple Point Shapefile

Method

  1. open GIS application
  2. add shapefile or raster layer to the map view
  3. zoom to the extent of the layer
  4. select buffer geoprocessing tool
  5. enter required parameters and options:
    1. input layer - the layer that the buffer operation will be applied to
    2. output layer - the new file that will be created and include the buffer features.
    3. distance - the distance from the input features that the buffer will be created at
    4. options - including the option to dissolve the resulting features by merging the buffer features together instead of retaining the individual buffer lines of overlapping buffer perimeters.

Examples

  1. Buffer with QGIS

Observations

  1. notes about what the student should notice about the results...


Overlay

Neighbourhoods

Map Algebra