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Operators and functions are used in expressions to calculate with data items and or constants.

Operators

An Operator is a symbolic presentation of a function to be applied on operands. Click here for the list of available operators.

Functions

Functions express dependence between two quantities, one of which is known and the other which is produced. A function associates a single output to each input element. Functions in the GeoDMS are categorized in the following function groups, corresponding to the table of contents:

  • Arithmeticbasic mathematical functions;
  • Orderingto compare/order data items;
  • Transcendental: which "transcends" algebra;
  • Conversion:  to convert data items to other value types/units or other notations;
  • Predicate:  to check certain conditions;
  • Aggregation:  to aggregate data items to other domain units;
  • Logical: to provide basic comparisons, returning in boolean items;
  • Relational: to join data items of different domain units;
  • Classify: to classify data items to class domains
  • Rescale:  to scale data items to new distributions;
  • Constant:  to define constant values;
  • Trigonometric: (also called circular functions) are functions of an angle;
  • Point: to calculate with single coordinate data items;
  • Sequence: to calculate with sequences of coordinates (arcs, polygons);
  • Network: to calculate with networks (nodes and links);
  • Grid: to calculate with grid (row/col) data;
  • String: to manipulate string data items;
  • File:  to perform file and folder operations;
  • MetaScript: to script iterations;
  • Allocation: to perform land use allocation;
  • Unit: to be applied on unit items;
  • Miscellaneous: miscellaneous.

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