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# deltaTime

The time interval, in seconds, to advance the simulation.

```
var deltaTime: Float
```

## Discussion

When [`mode`](/documentation/ComputeGraph/ComputeGraphSimulation/SimulationRate-swift.struct/mode-swift.property) is [`ComputeGraphSimulation.SimulationRate.Mode.fixedFrequency`](/documentation/ComputeGraph/ComputeGraphSimulation/SimulationRate-swift.struct/Mode-swift.enum/fixedFrequency)
or [`ComputeGraphSimulation.SimulationRate.Mode.fixedTime`](/documentation/ComputeGraph/ComputeGraphSimulation/SimulationRate-swift.struct/Mode-swift.enum/fixedTime), the simulation takes
between zero and [`maxSteps`](/documentation/ComputeGraph/ComputeGraphSimulation/AdvanceParams/maxSteps) fixed-size steps to consume this interval.
Any remaining time is accumulated and carried into the next advance.

---

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