`grid_size`(*type*: positive integer,*range*: any)-

Specifies the number of squares along each direction of the grid. `horizontal_wrap`(*type*: boolean,*range*: {`yes,no`})-

Specifies whether the grid wraps around in the horizontal direction. `vertical_wrap`(*type*: boolean,*range*: {`yes,no`})-

Specifies whether the grid wraps around in the vertical direction. `max_cells_per_process`(*type*: non-negative integer,*range*: any)-

Specifies an absolute population ceiling for the number of cells in the environment. `population_cutback_on_overcrowding`(*type*: real number,*range*: any)-

If the number of cells in the environment exceeds`max_cells_per_process`, then a proportion of the population, specified by`population_cutback_on_overcrowding`, is killed off. Cells to be killed are chosen stochastically, but based upon the number of energy tokens they have stored. `overcrowding_check_period`(*type*: positive integer,*range*: any)-

Specifies the period (expressed as a number of time slice sweeps) between successive checks for population overcrowding. `number_of_energy_tokens_per_grid_pos_per_sweep`-

(*type*: non-negative integer,*range*: any)

The average number of energy tokens distributed to each grid position at the beginning of each time slice sweep. The number of tokens distributed to individual squares may vary, as determined by the parameter`energy_distribution_scheme`. This parameter also determines the number of energy tokens taken away from each grid position at the end of each time slice sweep. See Section 4.7. `max_energy_tokens_per_grid_pos`(*type*: non-negative integer,*range*: any)-

The maximum number of free energy tokens that any square in the environment can store. If additional tokens are deposited on a square which already contains the maximum number allowed, the extra tokens are lost. `env_info_broadcast_period`(*type*: non-negative integer,*range*: any)-

Specifies the period (expressed as a number of time slice sweeps) between broadcasts of environmental information. See Section 4.5.6. `envinfostring_decay_constant`(*type*: real number,*range*: any)-

Governs the decay rate of messages in the environment. See Section 4.5.5. `envinfostring_decay_power`(*type*: real number,*range*: any)-

Governs the decay rate of messages in the environment. See Section 4.5.5. `envinfostring_lower_threshold`(*type*: real number,*range*: any)-

Specifies a threshold intensity for messages in the environment, below which they are deleted. See Section 4.5.5. `envinfostring_initial_intensity`(*type*: real number,*range*: any)-

Specifies the intensity assigned to newly created environmental messages. See Section 4.5.5. `max_time_for_msg_send_reinforcement`(*type*: non-negative integer,*range*: any)-

Specifies the maximum time interval (in number of time slices) in which a cell can reinforce the intensity of a message it has previously sent using the`cwm_send`instruction. See Section 4.5.5. `max_time_for_msg_receive_reinforcement`(*type*: non-negative integer,*range*: any)-

Specifies the maximum time interval (in number of time slices) in which a cell can extend the search area of a previously issued`rms_receive`instruction. See Section 4.3.7. `rms_receive_search_area`(*type*: non-negative integer,*range*: any)-

Specifies the number of squares searched for environmental messages upon each execution of the`rms_receive`instruction. See Section 4.3.7. `energy_collection_scheme`(*type*: enumerated,*range*: {`private,shared`})-

Specifies the rules governing the collection of energy tokens by a cell from the environment and from neighbouring cells. See Section 4.5.3. `energy_distribution_scheme`(*type*: enumerated,*range*: {`land,sea,mixed,random`})- Specifies how energy tokens are distributed across the environment by the Cosmos operating system at the beginning of each time slice sweep. See Section 4.5.2.
`energy_distribution_random_chunk_size`(*type*: non-negative integer,*range*: any)-

Specifies how many energy tokens are distributed to each randomly chosen square when`energy_distribution_scheme`is set to`random`. See Section 4.5.2. `x_delta`(*type*: real number,*range*: any)-

Specifies the energy gradient when`energy_distribution_scheme`is set to`land`(or`mixed`). See Section 4.5.2. `wave_width`(*type*: positive integer,*range*: any)-

Specifies the width of energy wave columns (expressed in number of squares) when`energy_distribution_scheme`is set to`sea`(or`mixed`). See Section 4.5.2. `number_of_waves`(*type*: positive integer,*range*: any)-

Specifies the number of energy waves, each of width`wave_width`, are fitted across the grid when`energy_distribution_scheme`is set to`sea`(or`mixed`). See Section 4.5.2. `land_fraction`(*type*: real number,*range*: 0.0-1.0)-

Determines the proportion of the environment to be treated as`land`when the parameter`energy_distribution_scheme`is set to`mixed`. An integer number of rows to be treated as`land`is calculated by rounding down the product of`land_fraction`and`grid_size`. These`land`rows are always at the top of the grid, and the`sea`rows at the bottom.

1999-05-29