(omega-user-driver)=

## Driver

The Omega Driver manages the execution of the Omega ocean model. Currently,
the only user-configurable parameters unique to the Driver relate to the
time management of the simulation.
```yaml
   TimeManagement:
      StartTime: 0001-01-01_00:00:00
      StopTime: none
      RunDuration: 0000_02:00:00.000
      CalendarType: No Leap
```
The `StartTime` and `StopTime` should be formatted strings in the form
`YYYY-MM-DD_HH:MM:SS.SSSS` and the `RunDuration` should be a formatted string in
one of the following forms:

- `DDDD_HH:MM:SS(.sss...)`
- `HH:MM:SS(.sss...)`
- `MM:SS(.sss...)`
- `SS(.sss...)`

The actual width of each unit can be arbitrary and the separators can be any
single non-numeric character. Either the
`StopTime` or `RunDuration` can be set to `none` in order to use the other to
determine the duration of the run. If both are set and `StopTime - StartTime`
is incosistent with `RunDuration`, then `RunDuration` is used for the
simulation. The supported calendar types are:
| Config option name | Calendar type |
| ------------------ | ------------- |
| Gregorian | Gregorian calendar |
| No Leap | Gregorian without leap years |
| Julian | Julian calendar |
| Julian Day | Julian day |
| Modified Julian Day | modified Julian day |
| 360 Day | 12 months, 30 days each |
| Custom | user-defined calendar |
| No Calendar | tracks elapsed time only |