Glossary

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A

active level
The capsule of a model project currently selected in the Capsule Set pane and displayed in the Model Canvas.
AgentVector
An aggregating component that manages its members as agents moving over a cartesian or hexagonal plane.
aggregator
Also aggregating container and aggregating component. Refers to CellMatrices, AgentVectors, SimWorlds, NodeNetworks and NetWorlds. Aggregators hold multiple instances of their elements and create a virtual topology within which the elements operate. Members of aggregating containers must be Capsules.
atomic component
Components such as Stocks, Terms, Flows, Commands, Codechips, etc., that do not have sub-components. They can only be members of Capsules.

C

Capsule
Prototype for a simulation unit. Capsules contain interacting base and aggregating components, and chips, and may contain inputs and outputs.
Capsule Interface
Also referred to as Interface. The set of DataInput and DataOutput components in a Capsule. They corrspond to pins in the enclosing Container.
capsule set:The window of the Application Interface where the capsules of a model are listed.
capture
A button that converts the visual representation of a Nova model into a script.
CellMatrix
An aggregating component that creates a two-dimensional cartesian or hexagonal topology with its members.
cellular automaton
A type of spatially explicit model where space is represented as a two-dimensional finite grid and each cell has a discrete state.
Chip
A Container component which contains a single Capsule for membership in a parent Capsule.
Clock
A special object for maintaining model time and providing strobe signals to the components.
Clocked Chip
A Chip with which a new Clock has been associated. Each strobe on the Chip produces a complete run of the enclosed Capsule instance based on the parameters of the associated Clock.
Codechip
A programmable component with user-specified inputs and outputs.
Command
A Nova component containing executable code that changes the state of the program.
component equation
Also called component expression. One or more lines of code included as a component property that defines the value of that component.
console
The window of the Application Interface where you can enter NovaScript commands one at a time.
Container
Chip or aggregator component. A Container holds one or more Capsule instances (or submodels). The latter are called elements or members of the Container
converter plug-in
A plug-in used to compute values used in updating the current state.
Coords
Refers to a JavaScript object that contains fields row and col, representing matrix row and column values.

D

delta value
The amount of time between state updates; also called dt.
deterministic model
A model where the outcome is fully predictable from the initial state (i.e., no random effects).
display plug-in
A plug-in used only for visualization.
dynamic systems model
A model of a system that changes over time.

E

Euler Method
A method of numeric integration that estimates P(t) as P(t-t) + P(t-t)t, where t is the change in time. Pronounced "Oiler method".

F

field
A property-name/property-value pair in a JavaScript object. Also refers to a stateful variable in a CodeChip.

G

global segment
Section of the Programming Window containing global definitions.

I

identifier
A text string (beginning with a letter) used as a property or local variable.
integration method
Procedure used to iterate from t to t + dt when considering continuous functions.
Interface
See Capsule Interface.
iteration
Step from time t to t + dt in the simulation.

L

local variable
An identifier used as a variable within a specific Capsule instance.
local variable segment
Section of the Programming Window containing local variables.

M

member
Constituent of a Container.
method
An object field that contains a function.
method segment
Section of the Programming Window containing local methods.
Model Canvas
The window of the Application Interface where the model is graphically designed and built from components.
model time
Local simulation time in units determined by the model.
Monte-Carlo
A model involving an element of chance (i.e., randomness).

N

NetViewer
A plugin used to visualize the nodes in a network; either a NodeNetwork or NetWorld.
NetWorld
An aggregating component that contains an AgentVector and NodeNetwork. The NodeNetwork determines the network topology where the agents exist.
NodeNetwork
An aggregating component that creates a network (i.e. mathematical graph) topology in which its members are nodes.
NovaScript
A scripting language that was created specifically for designing and running models. NovaScript is an extension of JavaScript.

P

parent
Another name for the host of an aggregator.
plug-in
A user-defined extension to Nova that adds a new component type.
post-processing (post-process)
Actions required during the post-update phase.
post-update
Actions taken after the current state is changed during an iteration.
pre-update
Actions taken before the current state is changed during an iteration.
primop
Short for primitive operator; a built-in JavaScript or NovaScript function.
Programming Window
The section of the Nova interface in which the user may add code.
project
All of the capsules, functions, clock settings, etc. associated with a model. When you open Nova, you are working on a project.
property
An identifier whose value is fixed throughout the simulation.
property segment
Section of the Programming Window containing local properties.

R

RunData
A special NovaScript object that contains all of the output from a Stock during a complete run. Used to accumulate statistics.
Runge-Kutta 2 Method
A method of numeric integration that employs a correction to each Euler method estimate.
Runge-Kutta 4 Method
A method of numeric integration, where each approximation is weighted average of four estimates.

S

schema or scenario
NovaScript object used for defining a component. Acts like a class declaration for NovaScript objects.
self
state object binding referencing the component object.
Self
Pointer to the state object of a simulator.
simulation
A sequence of state transitions from a start time to an end time using a fixed time increment dt.
simulator
Capsules, CellMatrices, AgentVectors SimWorlds, NodeNetworks and NetWorlds, all of which have constitutent members.
SimWorld
An aggregating component containing a CellMatrix and AgentVector, in which the CellMatrix serves as the cartesian or hexagonal space in which the AgentVector's agents exist.
start time
Point in model time when the simulation starts (usually 0).
State Object
A special object referenced from Self in a simulator. For Capsules, it contains the current value for each member; for aggregating components it provides methods for obtaining the state object of members.
stateful component
A component that keeps track of its value over time (e.g., Stock).
stateful plug-in
A plug-in with state-values that persist between iterations.
stateless component
A component that is only aware of its current value.
stochastic model
A model that exhibits random effects.
strobe
Action taken by each component at each iteration.
super
component object binding referencing an object's container.
Super
Pointer to the state object of the container of a simulator.

U

underscore.js
A library of very useful functions included in NovaScript; see http://underscorejs.org.

W

wrap
The practice of treating coordinates outside the dimension of a cartesian space as continuing from the opposite boundary. Topologically, the resulting space becomes a torus.