Issue with formula conversion
On Aug 27, 2014, at 12:44 PM, Gang Chen wrote:
Thanks for the help! However, I just need to get pdCompSymm(~1 + Age)
That's not a formula in the R sense of the word. You should do a better job of posting a use case. Perhaps you want an expression?
David.
>
> without a tilde (~) at the beginning.
>
> On Wed, Aug 27, 2014 at 3:34 PM, David Winsemius <dwinsemius at comcast.net> wrote:
>>
>> On Aug 27, 2014, at 11:19 AM, Gang Chen wrote:
>>
>>> A random effect formulation for R package nlme is read in as a string
>>> of characters from an input file:
>>>
>>> ranEff <- "pdCompSymm(~1+Age)"
>>>
>>> I need to convert 'ranEff' to a formula class. However, as shown below:
>>>
>>>> as.formula(ranEff)
>>> ~1 + Age
>>>
>>> the "pdCompSymm" is lost in the conversion. Any solutions?
>>
>> as.formula(paste("~",ranEff))
>> ~pdCompSymm(~1 + Age)
>> --
>>
>> David Winsemius
>> Alameda, CA, USA
>>
David Winsemius
Alameda, CA, USA