neighbour list in custom rate calculator

[gauravgoel82]

Does CustomRateCalculator class has neighbour list of the central coordinate available through backend?

1. In KMCLib/python/functest/IsingSpin/IsingSpinTest.py the rate function requires neighbours of the central coordinate at which a flip of spin is made. I've checked all the associated files and this information is not explicitly specified when calling the CustomRateCalculator. However, as per the calculations in the rate function, the elements_before and elements_after arrays should have the neighbours at indices 1-4.

2. Additionally, if the custom rate is for a diffusive hop on orthogonal lattice, e.g., in KMCLib/python/functest/OnTheFlyRateCalculator/OnTheFlyRateCalculatorTest.py, how the indices are defined for next nearest neghbours. Pasting the relevant portion from code below:

   Before move the central particle has neighbour indices 1, 2, 3, 4.

    # After the move the central particle has meighbour indices,
    # if we move to the right, 0, 7, 8, 12
    # if we move up,           0, 6, 8, 11
    # if we move down,         0, 5, 7, 10
    # if we move left,         0, 5, 6, 9