# denumerate

##### Transform an Allowable Formula for 'loglm' into one for 'terms'

`loglm`

allows dimension numbers to be used in place of names in
the formula. `denumerate`

modifies such a formula into one that
`terms`

can process.

- Keywords
- models

##### Usage

`denumerate(x)`

##### Arguments

- x
- A formula conforming to the conventions of
`loglm`

, that is, it may allow dimension numbers to stand in for names when specifying a log-linear model.

##### Details

The model fitting function `loglm`

fits log-linear models to
frequency data using iterative proportional scaling. To specify
the model the user must nominate the margins in the data that
remain fixed under the log-linear model. It is convenient to
allow the user to use dimension numbers, 1, 2, 3, ...for the
first, second, third, ..., margins in a similar way to variable
names. As the model formula has to be parsed by `terms`

, which
treats `1`

in a special way and requires parseable variable names,
these formulae have to be modified by giving genuine names for
these margin, or dimension numbers. `denumerate`

replaces these
numbers with names of a special form, namely `n`

is replaced by
`.vn`

. This allows `terms`

to parse the formula in the usual way.

##### Value

- A linear model formula like that presented, except that where
dimension numbers, say
`n`

, have been used to specify fixed margins these are replaced by names of the form`.vn`

which may be processed by`terms`

.

##### See Also

##### Examples

```
denumerate(~(1+2+3)^3 + a/b)
~ (.v1 + .v2 + .v3)^3 + a/b
```

*Documentation reproduced from package MASS, version 7.3-19, License: GPL-2 | GPL-3*