[R] Selective package installation

[Uwe Ligges]

On 18.05.2015 09:14, Partha Sinha wrote:
> I am using Win 7, 32 bit and R 3.2.0
>
> I want to install few packages via script.
> The script should first check if the package is already installed (I
> dont want update).

assume the packages are given in a character vector pkg.

pkg <- c("MASS", "A")

Then:

inst <- installed.packages()[,1]
install.packages(setdiff(pkg, inst))

Best,
Uwe Ligges





> If the package is already there , then it would go
> to the next package in my list.


> How can I do this ?
> Parth
>
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