-
Notifications
You must be signed in to change notification settings - Fork 0
Specs and Values
A spec defines the parameter space of an objective function. It is a tree structure where each node, called a spec node, defines a data type. Specs are provided by the user in YAML.
A value or individual (the two terms are used interchangeably) is a point in the parameter space. Values are instantiated by cambrian and provided to the objective function in form of a JSON.
An intuitive example is shown below. Provided are the content of a spec file, a graphical illustration of the tree structure, and a possible value. Details like the attributes can be ignored here. It suffices to mention here that anon map (anonymous map) is a recursive type, while real, int and bool are leaf types. Anonymous maps define resizable collections of a specific value type, in this case int.
Spec file content:
foo:
type: real
init: 0
scale: 1
bar:
type: bool
init: false
baz:
type: anon map
valueType:
type: int
init: 1
scale: 2
initSize: 2
Visual representation of spec tree:
(root)
/ | \
/ | \
/ | \
/ | \
real bool anon map
|
|
int
A possible value generated by cambrian:
{
"foo": 1.5,
"bar": false,
"baz": {
"0": 2,
"3": 11,
"4": 10
}
}
- Each type has 0 or more attributes (e.g.
scalein typereal). - Some attributes are mandatory (e.g.
scalein typereal) while others are optional (e.g.maxin typereal). - Types can be divided into two groups:
- leaf types:
real,int,bool,enum,const - recursive types:
sub,anon map,variant,optional
- leaf types:
- Each type has its own mutation behavior
- Recursive types each have their own crossover behavior
Below are links to the detailed explanations of each type, listing all corresponding attributes and describing the crossover (where applicable) and mutation logic. Each explanation will also contain examples for how a spec and a corresponding value might look like, and how the results of crossover and mutation might look like.