subject: Map Algebra Basics [print this page] Introduction to Map Algebra basics: Introduction to Map Algebra basics:
Map algebra is a simple and an elegant set based algebra for manipulating geographic data. Map algebra was introduced by Dr. Dana Tomlin in early 1980s. Tomlin proposed primitive operators for processing geographic data. Depending on the spatial neighborhood, operators are categorized into four groups: local, focal, zonal, and incremental. The input and output for each operator being map, the operators can be combined into a procedure to perform complex tasks.( source: wikipedia)
Components of (map) Algebra Basics:
The components of algebraic expressions from map algebra basics article
Variables,
Constants
Expression
Terms
Equation
Variables:
The variables can be defined as the characters, which are used for assigning the value. While reducing the algebraic equation value of the variable will be changed. mostly used variables are x, y, z.
Constant:
An algebraic constants are the value of a term whose value never change during the solving the algebraic equation. In 2y + 5, the value 5 is the constant.
Expressions:
An algebraic Expression is the set of variables, constant, coefficients, exponents, terms which are combined together by the following arithmetic operations
The below example is an algebraic expression :
2y + 5
Term:
Terms of the algebraic expression is grouped to form the algebraic expression by the arithmetic operations such as addition, subtraction, multiplication and division. In the following example 3n^2 + 2n the terms 3n^2, 2n are combined to form the algebraic expression 3n^2 + 2n by the addition operation ( + )
Coefficient:
The coefficient of an algebraic expression is the term is present just before the terms. From the following example, 3n2 + 2n the coefficient of 3n2 is 3 and 2n is 2
Equations:
An algebraic equation equate the numbers or expressions. Algebraic equation is the only thing which is used for the value of the variable. The example of the equation is given below
