[R] Rare behaviour for nlme::reStruct example and question about ?lmeObject

[Martin Maechler]

>>>>> Iago  
>>>>>     on Thu, 17 Nov 2022 11:53:31 +0100 writes:

    > Thank you Martin,
    > Regarding my question about `terms`, I meant the `terms` component of 
    > the `lme` output. For example, for

    > fm1 <- lme(distance ~ age, data = Orthodont)

    > I can see through str(fm1), the next:

    > $ terms       :Classes 'terms', 'formula'  language distance ~ age
    >   .. ..- attr(*, "variables")= language list(distance, age)
    >   .. ..- attr(*, "factors")= int [1:2, 1] 0 1
    >   .. .. ..- attr(*, "dimnames")=List of 2
    >   .. .. .. ..$ : chr [1:2] "distance" "age"
    >   .. .. .. ..$ : chr "age"
    >   .. ..- attr(*, "term.labels")= chr "age"
    >   .. ..- attr(*, "order")= int 1
    >   .. ..- attr(*, "intercept")= int 1
    >   .. ..- attr(*, "response")= int 1
    >   .. ..- attr(*, ".Environment")=<environment: R_GlobalEnv>
    >   .. ..- attr(*, "predvars")= language list(distance, age)
    >   .. ..- attr(*, "dataClasses")= Named chr [1:2] "numeric" "numeric"
    >   .. .. ..- attr(*, "names")= chr [1:2] "distance" "age"

    > However, there is no paragraph for this component among those in 
    > ?lmeObject (in the Value section) as there is for fixDF, apVar, call, 
    > etc.. If not needed, I assume the explanation would be that `terms` does 
    > not need to be included in a legitimate ´"lme"´ object'.

    > Kind regards,
    > Iago

I see; now I understand what you meant. I've taken time to check and
found that the 'terms' part *is* needed, even though not for the
simplest methods such as summary(), residuals(), ..  and so have
added it to the  ?lmeObject  help page for the next version of
nlme.

Thank you, Iago!

Best,
Martin