Neutral Model Data (neutral.dat)

If the parameter record_neutral_model_data is set to yes, Cosmos will record data about the run in the file neutral.dat. The period between successive updates to this file is set by the parameter neutral_model_data_export_period. The data in neutral.dat can subsequently be used to run a neutral shadow of the run (see the description of the parameter run_neutral_model in Section A.1). The first two lines of the file are a header: the first line records the size of the environment (as specified by the parameter grid_size), the number of organisms with which the system was inoculated at the start of the run (as specified by the parameter number), and the maximum number of cells allowed in a multicellular organism (as specified by the parameter max_cells_per_organism); and the second line is a separator. Each subsequent line of the file is of the format:

TimeSliceNumber NewSpecies OrganismBirths CellSplitInfo CellDeathInfo
OrganismFissionInfo OrganismMovementInfo

where NewSpecies is the number of new species that have appeared in the population in the period since the previous line of the file was recorded; OrganismBirths is the number of new organisms that were born in that period; CellSplitInfo shows the number of organisms which grew in size (by executing the instruction nwm_split), followed by a list of the size (in terms of number of cells--before the cell division) of each such organism; CellDeathInfo shows the number of cells that died, followed by a list of the size (before the cell death) of the organism to which each one belonged; OrganismFissionInfo shows the number of organisms which fissioned (due to cell death), followed, for each one, by the number of fragments (new organisms) that resulted from the fission, and a list of the size of each new organism; and the final block of information, OrganismMovementInfo, shows the number of organisms which moved, followed, for each one, by a triplet of numbers indicating the size of the organism, and the x and y components of its movement.