Simulation.Aivika.Dynamics.Var

Tested with: GHC 7.0.3

This module defines a variable that is bound to the event queue and that keeps the history of changes storing the values in an array.

Documentation

data Var a

Like the Ref reference but keeps the history of changes in different time points. The Var variable is safe in the hybrid simulation and when you use different event queues, but this variable is slower than references.

varQueue :: Var a -> EventQueue

Return the bound event queue.

varChanged :: Var a -> Signal a

Return a signal that notifies about every change of the variable state.

varChanged_ :: Var a -> Signal ()

Return a signal that notifies about every change of the variable state.

newVar :: EventQueue -> a -> Simulation (Var a)

Create a new variable bound to the specified event queue.

readVar :: Var a -> Dynamics a

Read the value of a variable, forcing the bound event queue to raise the events in case of need.

writeVar :: Var a -> a -> Dynamics ()

Write a new value into the variable.

modifyVar :: Var a -> (a -> a) -> Dynamics ()

Mutate the contents of the variable, forcing the bound event queue to raise all pending events in case of need.

freezeVar :: Var a -> Dynamics (Array Int Double, Array Int a)

Freeze the variable and return in arrays the time points and corresponded values when the variable had changed.