[R] How to remove the double or single quote from a string(unquote?)?

[Gerrit Eichner]

Hi, Jing Jiang,

maybe

as.formula( paste( "V12 ~ V", i, sep = ""))

inside the call to glm() does what you need.

Hth  --  Gerrit


On Tue, 19 Apr 2011, JingJiang Yan wrote:

> Is there a function to get a string without a pair of quotes around it?
>
> I have several expressions like:
> glm(V12 ~ V3, family=binomial, data=df1)
> glm(V12 ~ V4, family=binomial, data=df1)
> ...
> glm(V12 ~ V8, family=binomial, data=df1)
>
> As you can see, the only differences among them are V3 ... V8.
> Because sometimes several of these expressions are performed many times,
> I want to use a variable "i" to change the V3 ... V8. I did this with:
>
>> i <- 3:8
>> glm(V12 ~ paste("V", i, sep=""), family=binomial, data=df1)
>
> However, it seems the paste always returns a variable name with a pair of 
> quotes, which were wrong in such condition.
> I only find a function "sQuote" to add quotes to a string, and it looks I am 
> looking for an opposite function of it.
> Any advice will be appreciated.
>
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