GIS Dictionary

Browse dictionary

filter

URL copied Share URL
  1. [data analysis] A constraint or set of constraints used to limit data to a subset. For example, in a map layer of global cities, set a filter to show only cities in Nigeria.
  2. [spatial analysis] On a raster, an analysis boundary or processing window within which cell values affect calculations and outside which they do not. Filters are used mainly in cell-based analysis where the value of a center cell is changed to the mean, the sum, or some other function of all cell values inside the filter. A filter moves systematically across a raster until each cell has been processed. Filters can be of various shapes and sizes, but are most commonly three-cell by three-cell squares. Media/filter.gif
  3. [data management] A GIS operation used to hide (but not delete) features in a map document or attribute table.

See also