[R] How to use bash command in R script?

[Peter Dalgaard]

Guo Wei-Wei wrote:
> Dear All:
>
> Maybe it is a too basic question, but I don't how to find the answer.
> Sorry for that.
>
> What I want to do is call a shell command, which will provide two
> numbers, and assign those numbers to a vector. For example:
>
> The following command:
>
> $mxresult.sh ABC.mx
>
> mxresult.sh is a script written by myself and ABC.mx is a Mx script.
> I can get two numbers, 126.128 and 29, with this command.
>
> Is there any way to do it like this:
>
> c <- somefunction("mxresult.sh ABC.mx")
>
> Or is their any other way to fulfill the function?
>   
txt <- system(""mxresult.sh ABC.mx", intern=TRUE)

is the first step.  Then you need to get the numbers using either a 
scan() on a textConnection (see its help page) or something like

mynum <- as.numeric(strsplit(txt, "  *")[[1]])


> Thanks in advance!
>
> Best washes,
> Wei-Wei
>
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