Ps-i 2.4 - attributes

General description

An attribute is a quality of a particular agent. It can be expressed as a number, a true/false value or something more comlex.

Section format

The following is an example describing attribute influence:

attribute 'influence'
	type int
	smallest 0
	largest 1000
	default 1
end

As you can see the attribute section starts with the keyword attribute that is followed by the name of this particular attribute. Then we see a series of keywords followed by parameters. The section is completed with keyword end.

Available keywords
Keyword	Value	Attribute type	Description
`type`	`int`, `bool`, `repertoire`, set		Declares type of the attribute. Should be followed by one of `bool`,`int`, `set` or `repertoire`. Note: currently `set` is not fully implemented
`default`	e.g. 10	any	Specifies default value (optional)
`smallest`	e.g. -3	`int`	Specifies smallest possible value
`largest`	e.g. 200	`int`	Specifies largest possible value
`size`	e.g. 10	`set`, `repertoire`	Specifies size of the `set` or `repertoire`. Limited to `64` for sets and `56` for repertoires.
`bias_min`	e.g. 4	`repertoire`	minimum possible value for bias. (valid only for attributes of type `repertoire`)
`bias_max`	e.g. -3	`repertoire`	maximum possible value for bias. (valid only for attributes of type `repertoire`)
`bias_vol`	e.g 500	`repertoire`	likelihood that a given bias value will change on this timestep. (in units of 0.01%) (valid only for attributes of type `repertoire`)
`walk`	no argument	`repertoire`	during evolution a particular bias value can only change by +1 or -1 during one timestep
`jump`	no argument	`repertoire`	during evolution a particular bias value can change to any possible value during one timestep
`bias_values`	e.g. 1,-1,2,3	`repertoire`	this keyword is used to specify initial bias values. it is only used in snapshots and will _never_ be accessed if loading as a model.
`bias_init_routine`	e.g. `"bias_init"`	`repertoire`	specifies a routine to define initial values for bias
`bias_update_routine`	e.g. `"bias_update_jump"`	`repertoire`	Specifies a routine for updating bias values. When present, keywords jump, walk, bias_max, bias_min and bias_vol are disregarded.

More examples

attribute 'immutable'
	type bool
	default false
end

routine 'bias_init' composite
	comment 'This sets initial biases to zero for all identities except first'
	when "$1==1"  "-1"
	default "0"
end

routine 'bias_update1' composite
	comment 'Set 2 to 0 always, otherwise jump randomly between -5 and 4'
	when "$1==2" "0"
	default "(rand/1000)-5"
end

attribute 'cache'
	type repertoire
	walk
	size 20
	bias_max 2
	bias_min -2
	bias_vol  500
	default empty
	bias_init_routine "bias_init"
	bias_update_routine "bias_update1"
end

Ps-i 2.4 - attributes

General description

Section format

More examples

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