Glossary for Geospatial Science

variable:� (in database queries) �A named entity that has an assigned value.� There are four kinds of query variables: (1) those are associated with the vector elements (like numlines, class, and startnode); (2) those which are fields from a database (perhaps Name, Acres, and Yield); (3) those which control the drawing styles of vector elements (like size, color, and fillcolor); and (4) the ten temporary user variables for numeric operations (temp0, temp1, temp2 ... temp9).� For example, the point element variable �size� can have a value from 1 to 64.� It controls the size at which a point element is drawn.� An assignment statement can change only the values of drawing style and temporary variables; it cannot change the value of variables that are associated with a vector element or a database.