R: Create intervention objects from Rx input

ev_rx {mrgsolve} | R Documentation

## Create intervention objects from Rx input

### Description

See details below for Rx specification. Actual parsing is done by parse_rx; this function can be used to debug Rx inputs.

### Usage

    ev_rx(x, y, ...)

    ## S4 method for signature 'mrgmod,character'
    ev_rx(x, y, ...)

    ## S4 method for signature 'character,missing'
    ev_rx(x, df = FALSE, ...)

    parse_rx(x)

### Arguments

`x` | a model object or `character` Rx input
`y` | `character` Rx input; see details
`...` | not used at this time
`df` | if `TRUE` then a data frame is returned

### Value

The method dispatched on model object (`mrgmod`) returns another model object. The `character` method returns an event object. The `parse_rx` function return a list named with arguments for the event object constructor ev.

### Rx specification

- The dose is found at the start of the string by sequential digits; this may be integer, decimal, or in scientific notation

- Use `in` to identify the dosing compartment number; must be integer

- Use `q` to identify the dosing interval; must be integer or decimal number (but not scientific notation)

- Use `over` to indicate an infusion and its duration; integer or decimal number

- Use `x` to indicate total number of doses; must be integer

- Use `then` or `,` to separate dosing periods

- User `after` to insert a lag in the start of a period; integer or decimal number (but not scientific notation)

### Examples

    # example("ev_rx")

    ev_rx("100")

    ev_rx("100 in 2")

    ev_rx("100 q12 x 3")

    ev_rx("100 over 2")

    ev_rx("100 q 24 x 3 then 50 q12 x 2")

    ev_rx("100 then 50 q 24 after 12")

    ev_rx("100.2E-2 q4")

    ev_rx("100 over 2.23")

    ev_rx("100 q 12 x 3")

    parse_rx("100 mg q 24 then 200 mg q12")

[Package mrgsolve version 1.0.4 Index]