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SOMORJAI

This program (version 2.4) computes the averaged nearest neighbour distances for different values of $k$, $N$ and $\gamma$. To randomly select reference points and neighbours, the first step is to scramble the vector indices. The last index is used for the reference point. The distances are computed between the reference point and $N$ other points where $N$ varies according to the specified operation method (see section 3.3). Distances between points that are close in time can be discarded (Theiler correction, see Chapter 6). The distances are sorted according to their magnitude. In fact sorting could be done at each time that a distance has been computed, so that the neighbours up to the largest required one are sorted while the rest remains unsorted. However, one call to a sort routine [Singleton, 1969] for every reference point turned out to be the most efficient. The distances to the specified neighbours are stored and weighted with $\gamma$. A next reference point is obtained by swapping the current one with a new one and scramble the remaining indices again. The program has an option to choose reasonable values for $k$ and $N$ automatically.


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