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Create a new observer

create_observer.Rd

Create a single Observer from named arguments. This is a thin factory around Observer$new() that builds the raw list shape for you and composes with create_observer_set() via create_observer_set(observers = list(...)).

An observer is a simulation-time formula that computes a derived quantity from the underlying model (for example an amount observer or a container observer). It is not itself a building block; it lives inside an ObserverSet.

Usage

create_observer(
  name,
  type,
  dimension = NULL,
  formula = NULL,
  formula_references = NULL,
  container_criteria = NULL,
  molecule_list = NULL
)

Arguments

name

Character. Name of the observer (required).

type

Character. The observer type, one of "Amount" (an AmountObserverBuilder) or "Container" (a ContainerObserverBuilder). Any other value aborts (required).

dimension

Character. The dimension of the observed quantity. Omitted when NULL.

formula

The observer's formula. Either a bare expression string (which becomes the inner Formula$Formula), or a full ExplicitFormula raw list used as the whole Formula. Omitted when NULL.

formula_references

List of formula references, each a create_formula_reference() output or an equivalent raw {Alias, Path, Dimension} list. Written to the formula's References; supplying these without formula yields a Formula carrying only References. When formula is a full ExplicitFormula list that already carries its own References, this argument overrides them. Omitted when NULL.

container_criteria

List of container criteria, each a create_descriptor_condition() output or an equivalent raw {Tag, Type} list. Written to ContainerCriteria. Omitted when NULL.

molecule_list

A create_molecule_list() output or an equivalent raw list. Written to MoleculeList. Omitted when NULL.

Value

An Observer object.

Examples

# Minimal amount observer
create_observer(name = "drug_amount", type = "Amount")
#> 
#> ── Observer: drug_amount 
#> • Type: Amount

# Container observer with all sub-properties
obs <- create_observer(
  name = "brain_plasma_conc",
  type = "Container",
  dimension = "Concentration (molar)",
  formula = "Conc_Br",
  formula_references = list(
    create_formula_reference(
      "Conc_Br",
      "Organism|Brain|Plasma|Drug|Concentration"
    )
  ),
  container_criteria = list(
    create_descriptor_condition("Brain", "InContainer")
  ),
  molecule_list = create_molecule_list(for_all = FALSE, include = "Drug")
)

# Compose into an observer set
create_observer_set(name = "BrainPlasmaConcentration", observers = list(obs))
#> 
#> ── ObserverSet: BrainPlasmaConcentration ───────────────────────────────────────
#> • 1 observer