## Usage

```
# S3 method for PMmatrix
summary(object, formula, FUN, include, exclude, ...)
```

## Arguments

- object
A PMmatrix object which is the

`$data`

field of a PM_data object, but can also be loaded by PMreadMatrix or PM_load.- formula
Optional formula for specifying custom summaries. See aggregate and formula for details on how to specify formulae in R. If, for example, the data contain a covariate for weight named 'wt', then to summarize the mean dose in mg/kg per subject specify

`formula = dose/wt ~ id`

and`FUN = mean`

.- FUN
The summary function to apply to formula, if specified.

- include
A vector of subject IDs to include in the summary, e.g.

`c(1:3,5,15)`

- exclude
A vector of subject IDs to exclude in the summary, e.g.

`c(4,6:14,16:20)`

- ...
Additional arguments to

`FUN`

, e.g.`na.rm = TRUE`

## Value

A list of class *summary.PMmatrix* with the summary of the PMmatrix object,
containing the following items:

- nsub
Number of subjects

- ndrug
Number of drug inputs

- numeqt
Number of outputs

- nobsXouteq
Number of observations by outeq

- missObsXouteq
Number of missing observations by outeq

- ncov
Number of covariates

- covnames
Covariate names

- ndoseXid
Number of doses per input per subject

- nobsXid
Number of observations per outeq per subject

- doseXid
Doses per input per subject

- obsXid
Observations per outeq per subject

- formula
Results of including formula