Guided random walk

The new unknown, F, must satisfy an equation slightly more complicated than Eq. (2.8). is assumed to have the same nodes as F, and F is therefore non-negative. Typical calculations embrace 1000 walkers, each of which take 104 to 105 steps, each of length 10-2 to 10 4 atomic units of time. The guided random walks are run until a steady distribution of walkers is reached. A solution consists of a table of set 3n coordinates for each walker, and the corresponding distribution of walkers replicates F. 

R. Metzler and J. Klafter, The random walk s guide to anomalous diffusion A fractional dynamics approach. Phys. Rep. 339, 1 (2000). 

Another fundamental distinction is based on whether an organism is able to make turns in its motion path, which will direct it toward its destination. Depending on the characteristics of the stimulus and the abilities of the microorganism, guiding may be direct, in the sense of taking a straight-line path to the destination, or indirect, as in the case of a biased random walk, to reach the vicinity of the destination. 

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