writeModel {BRugs} | R Documentation |

## Creating an OpenBUGS model file

### Description

Convert R function to an OpenBUGS model file

### Usage

```
writeModel(model, con = "model.txt", digits = 5)
```

### Arguments

`model` |
R function containing the BUGS model in the BUGS model language, for minor differences see Section Details. |

`con` |
passed to |

`digits` |
number of significant digits used for BUGS
input, see |

### Details

The fact that bugs models follow closely to S (R) syntax is used. It should be possible to write most BUGS models as R functions.

As a difference, BUGS syntax allows truncation specification like this:
`dnorm(...) I(...)`

but this is illegal in R. To overcome this incompatibility, use `%_%`

before `I(...)`

:
`dnorm(...) %_% I(...)`

.
The dummy operator `%_%`

will be removed before the BUGS code is saved.

### Value

Nothing, but as a side effect, the model file is written.

### Author(s)

original idea by Jouni Kerman, modified by Uwe Ligges

### See Also

### Examples

```
## Same "ratsmodel" that is used in the examples in ?BRugs and ?BRugsFit:
ratsmodel <- function(){
for(i in 1:N){
for(j in 1:T){
Y[i, j] ~ dnorm(mu[i, j],tau.c)
mu[i, j] <- alpha[i] + beta[i] * (x[j] - xbar)
}
alpha[i] ~ dnorm(alpha.c, alpha.tau)
beta[i] ~ dnorm(beta.c, beta.tau)
}
tau.c ~ dgamma(0.001, 0.001)
sigma <- 1 / sqrt(tau.c)
alpha.c ~ dnorm(0.0, 1.0E-6)
alpha.tau ~ dgamma(0.001, 0.001)
beta.c ~ dnorm(0.0, 1.0E-6)
beta.tau ~ dgamma(0.001, 0.001)
alpha0 <- alpha.c - xbar * beta.c
}
## some temporary filename:
filename <- file.path(tempdir(), "ratsmodel.txt")
## write model file:
writeModel(ratsmodel, filename)
## and let's take a look:
file.show(filename)
```

*BRugs*version 0.9-2.1 Index]