gRbase (version 2.0.3)

array-simulate: Simulate data from array.

Description

Simulate data (slice of) an array: Simulate n observations from the array x conditional on the variables in margin (a vector of indices) takes values given by margin.value

Usage

simulateArray(x, nsim = 1, margin, value.margin, seed = NULL)
# S3 method for table
simulate(object, nsim = 1, seed = NULL, margin, value.margin, ...)
# S3 method for xtabs
simulate(object, nsim = 1, seed = NULL, margin, value.margin, ...)
# S3 method for array
simulate(object, nsim = 1, seed = NULL, margin, value.margin, ...)

Value

A matrix.

Arguments

x, object

An array.

nsim

Number of cases to simulate.

margin, value.margin

Specification of slice of array to simulate from.

seed

Seed to be used for random number generation.

...

Additional arguments, currently not used.

Author

Søren Højsgaard,

Examples

## 2x2 array
x <- parray(c("a", "b"), levels=c(2, 2), values=1:4)

x <- tabNew(c("a", "b"), levels=c(2, 2), values=1:4)

## Simulate from entire array
s <- simulateArray(x, 1000)
xtabs(~., as.data.frame(s))

## Simulate from slice defined by that dimension 1 is fixed at level 2
s <-simulateArray(x, 1000, margin=1, value.margin=2)
xtabs(~., as.data.frame(s))

## 2 x 2 x 2 array
x <- parray(c("a", "b", "c"), levels=c(2, 2, 2), values=1:8)
## Simulate from entire array
s <-simulateArray(x, 36000)
xtabs(~., as.data.frame(s))

## Simulate from slice defined by that dimension 3 is fixed at level 1
s <-simulateArray(x, 10000, 3, 1)
xtabs(~., as.data.frame(s))