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A contour line, of a function of two variables, is a curve along which the function has a constant value. In cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. A contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness of slopes. The contour interval of a contour map is the difference in elevation between successive contour lines. More generally, a contour line for a function of two variables is a curve connecting points where the function has a same particular value. The gradient of the function is always perpendicular to the contour lines. When the lines are close together the length of the gradient is large: the variation is steep. ... more
System Design Strategies
System Design Strategies is an exclusive resource for the successful design and deployment for geographic information systems technology. This documentation is provided to share system architecture design methodology and the fundamental principles that contribute to system performance and scalability.