R: Obtain a list of collapsed networks sampled periodically from...

get.networks {networkDynamic} | R Documentation

## Obtain a list of collapsed networks sampled periodically from a networkDynamic object

### Description

Given a start time, end time, and increment (or vectors of onsets and termini) to express sampling intervals, return a list of collapsed networks from a networkDynamic object.

### Usage

      get.networks(dnet, start = NULL, end = NULL, time.increment = NULL,
                   onsets=NULL, termini=NULL,...)

### Arguments

`dnet` | A `networkDynamic` object with possible vertex, edge, network, and attribute spell information.
`start` | numeric value giving the start of the sampling interval
`end` | numeric value giving the end of the sampling interval
`time.increment` | value for the offset (and duration) between sucessive samples. Will default to 1 if not otherwise specified
`onsets` | A numeric vector containing the onset times of the networks to be extracted. This must be accompanied by `termini` of the same length.
`termini` | A numeric vector containing the terminus times of the networks to be extracted. This must be accompanied by `onsets` of the same length.
`...` | Additional arguments to `network.collapse` (such as `rule`,`active.default`,`retain.all.vertices`)

### Details

The sampling ("slicing") intervals may be defined using either the `start`, `end`, and `time.increment` parameters, or by providing parallel vectors of `onsets` and `termini`. If values are not specefied but a `net.obs.period` attribute exists to describe the 'natural' sampling parameters, `start` and `end` will defult to the max an min of the observations element, with `time.increment` set to its corresponding value in the `net.obs.period`.

### Value

A `list` of static `network` objects corresponding to the specified sampling intervals of the `networkDynamic`

### Note

See Note in `network.collapse`.

### Author(s)

Kirk Li, Skye Bender-deMoll

### See Also

See Also as `network.collapse` for obtaining a slice of static network, `network.extract` for extracting sub-ranges of a networkDynamic, `get.vertex.attribute.active` for more on TEA attributes, and `as.network.networkDynamic` for stripping the the networkDynamic class from an object.

### Examples

    # create a networkDynamic with some basic activity and time extended attributes (TEA)
    test <- network.initialize(5)
    add.edges.active(test, tail=c(1,2,3), head=c(2,3,4),onset=0,terminus=1)
    activate.edges(test,onset=3,terminus=5)
    activate.edges(test,onset=-2,terminus=-1)
    activate.edge.attribute(test,'weight',5,onset=3,terminus=4)
    activate.edge.attribute(test,'weight',3,onset=4,terminus=5,e=1:2)

    # obtain the list of networks
    list <- get.networks(test,start=0, end=5)

    # aggregate over a longer time period with specified rule
    list <- get.networks(test,start=0, end=6,time.increment=2,rule='latest')

    # use 'at' style extraction of momentary slices via onsets & termini
    list <- get.networks(test,onsets=0:5,termini=0:5)

    # ensure that all networks returned will be the same size
    list <- get.networks(test,onsets=0:5,termini=0:5,retain.all.vertices=TRUE)

    # find out how many edges in each sampling point with apply
    sapply(get.networks(test,start=0,end=5),network.edgecount)

    # generate a list of matrices
    lapply(get.networks(test,start=0,end=5),as.matrix)

[Package networkDynamic version 0.9.0 Index]