# Ordinary Differential Equations

### Description

`ode.model`

is the system evaluation function called when an $ODE block
is detected in the model file, indicating that the model is defined by
ordinary differential equations. `ode.model`

is typically not called
directly by users

### Usage

1 2 3 4 5 6 7 8 9 10 |

### Arguments

`parms` |
A vector of primary parameters. |

`derparms` |
A list of derived parameters, specified in the $DERIVED block of code. |

`code` |
A list of R code extracted from the model file. Depending on content of the model file, the levels of this list could be: template, derived, lags, ode, dde, output, variance, and/or secondary. |

`bolus` |
A data.frame providing the instantaneous inputs entering the system of delay differential equations for the treatment and individual being evaluated. |

`infusion` |
A data.frame providing the zero-order inputs entering the system of delay differential equations for the treatment and individual being evaluated. |

`xdata` |
A vector of times at which the system is being evaluated. |

`covdata` |
A data.frame of covariate data for the treatment and individual being evaluated. |

`issim` |
An indicator for simulation or estimation runs. |

`check` |
An indicator whether checks should be performed to validate function inputs. |

`options` |
A list of differential equation solver options. Currently not modifiable by users. |

### Details

`ode.model`

evaluates the model for each treatment of each individual
contained in the dataset using several utility functions: `derived.parms`

,
`init.cond`

, `input.scaling`

, `make.dosing`

, `init.update`

,
and `de.output`

.

The actual evaluation of the system is performed by `ode`

from the
deSolve package.

### Value

Returns a matrix of system predictions.

### Author(s)

Sebastien Bihorel (sb.pmlab@gmail.com)

### See Also

`ode`

,
`init.cond`

, `input.scaling`

,
`make.dosing`

, `init.update`

,
`de.output`