Flooding algorithm

A flooding algorithm is an algorithm for distributing material to every part of a graph. The name derives from the concept of inundation by a flood.

Flooding algorithms are used in computer networking and graphics. Flooding algorithms are also useful for solving many mathematical problems, including maze problems and many problems in graph theory.

A flooding algorithm is an algorithm for distributing material to every part of a connected network. The name derives from the concept of inundation by a flood.

Flooding algorithms are used in systems such as Usenet and peer-to-peer file sharing systems and as part of some routing protocols, including OSPF, DVMRP, and those used in ad-hoc wireless networks.

There are several variants of flooding algorithm: most work roughly as follows.

Each node acts as both a transmitter and a receiver. Each node tries to forward every message to every one of its neighbors. This results in every message eventually being delivered to all reachable parts of the network.

Real-world flooding algorithms have to be more complex than this, since precautions have to be taken to avoid wasted duplicate deliveries and infinite loops, and to allow messages to eventually expire from the system.

Flooding algorithms are also useful for solving many mathematical problems, including maze problems and many problems in graph theory.

Flow based routing algo

Following the interpolation and pre-processing of the DEM, CatchmentSIM applies a flow routing algorithm to delineate subcatchment boundaries, determine the subcatchment network relationship and calculate geophysical subcatchment properties.

The flow routing algorithm forms the basis of all these processes and is consequently, of vital importance to the quality of any GIS based hydrologic investigation. CatchmentSIM utilises an adapted form of the 'rolling ball' flow-path methodology first proposed by Lea (1992) . This algorithm determines a downslope flow angle for each pixel that can be anywhere in the range of 0-360 degrees. The flow direction angle is determined as the resultant flow vector from the combination of the steepest non-diagonal pixel flow path and the next steepest adjacent non-diagonal flow-path Flow from each pixel is then routed through all downhill pixels until the catchment outlet (or DEM boundary) is reached. The algorithm treats the flow-path as a line and records the entry and exit points of the flow-path through all pixels.